R v Owens - [2025] SASCA 96

SUPREME COURT OF SOUTH AUSTRALIA
(Court of Appeal: Criminal)
R v OWENS
[2025] SASCA 96
Judgment of the Court of Appeal
(The Honourable President Livesey, the Honourable Justice David and the Honourable Justice Stanley)
25 August 2025
CRIMINAL LAW - APPEAL AND NEW TRIAL - INTERFERENCE WITH DISCRETION OR FINDING OF JUDGE
CRIMINAL LAW - PARTICULAR OFFENCES - DRUG OFFENCES - DEALING AND DISTRIBUTION OF DRUGS - TRAFFICKING OR SALE AND SUPPLY
CRIMINAL LAW - EVIDENCE - JUDICIAL DISCRETION TO ADMIT OR EXCLUDE EVIDENCE
This is an application by the Director of Public Prosecutions (SA) (‘the Director’) for permission to appeal against an interlocutory order made by a Judge of the District Court excluding evidence obtained during a traffic stop. The application is made pursuant to s 157(1)(e) of the Criminal Procedure Act 1921 (SA) (‘the CPA’).
The respondent was charged with two counts of trafficking in a controlled drug, contrary to s 32(3) of the Controlled Substances Act 1984 (SA) (‘the CSA’). After stopping the respondent’s vehicle and administering an alcotest, police officers searched the vehicle and seized methylamphetamine (the subject of Count 1) and 3,4-methylenedioxyamphetamine (MDA) (the subject of Count 2).
On 4 October 2024, the respondent filed an interlocutory application, alleging the traffic stop was unlawful and seeking exclusion of all evidence seized by the police officers. During the voir dire hearing, the prosecution called the two police officers involved in the traffic stop. The respondent alleged that the police officers used the powers under ss 47E(2) and 40H of the Road Traffic Act1961 (SA) (‘the RTA’) as a pretext to investigate allegations of unlawful drug activity contained in intelligence briefings.
On 15 April 2025, the Judge ordered that the evidence be excluded in the exercise of the public policy discretion. The Judge held that the sole purpose of the police officers’ decision to stop the respondent’s vehicle was for the ‘ulterior purpose’ of investigating unlawful activity described in intelligence briefings rather than to administer an alcotest. The Judge held the traffic stop was unlawful.
The Director sought permission to appeal against the interlocutory order on the following grounds:
1. The Judge erred in her construction of the powers contained in ss 47E(2) and 40H of the RTA and made erroneous factual findings in determining that the stopping of the respondent’s vehicle was unlawful.
2. Further, or in the alternative, the Judge erred in the exercise of her discretion to exclude the evidence.
Held, per the Court, granting permission to appeal and allowing the appeal:
1. The factual finding by the Judge that the police stopped the vehicle for the sole purpose of investigating the unlawful activity described in the intelligence briefings was erroneous. The police officers lawfully exercised their power under s 47E of the RTA to stop the vehicle. They also had the power to do so under ss 40H of the RTA and s 96 of the Motor Vehicles Act 1959 (SA).
2. The Judge’s order excluding the evidence is set aside.
3. The interlocutory application dated 4 October 2024 is dismissed.
Controlled Substances Act 1984 (SA) ss 32(3), 52, 52A; Criminal Procedure Act 1921 (SA) s 157, 157(1)(e), 157(3), 157(3)(a); Motor Vehicles Act 1959 (SA) ss 91(5), 91(5)(a), 96; Road Traffic Act 1961 (SA) ss 40H, 40V, 47E; Summary Offences Act 1953 (SA) s 68, referred to.
R v Owens [2025] SADC 38, discussed.
Bunning v Cross (1978) 141 CLR 54; Dearman v Dearman (1908) 7 CLR 549; Fox v Percy (2003) 214 CLR 118; Jovanovic v Rossi (1985) 58 ALR 519; Moran v McMahon (1985) 3 NSWLR 700; R v Kola (2002) 83 SASR 477; R v Neal [2017] SASCFC 44; R v Romeo (1982) 30 SASR 243; Taylor v Johnson (1983) 151 CLR 422; The Glannibanta (1876) 1 PD 283; Warren v Coombes (1979) 142 CLR 531, considered.

R v OWENS
[2025] SASCA 96
Court of Appeal – Criminal: Livesey P, David and Stanley JJA

THE COURT: The Director of Public Prosecutions (SA) (‘the Director’) seeks permission to appeal against an interlocutory order made by a Judge of the District Court excluding evidence obtained from a search of the respondent’s vehicle. The Director applies pursuant to s 157(1)(e) of the Criminal Procedure Act 1921 (SA) (‘the CPA’) on the basis that the decision destroys or substantially weakens the prosecution case in respect of the charges, and, if correct, is likely to lead to abandonment of the charges.[1]
[1] Criminal Procedure Act 2021 (SA) s 157(3)(a).
The respondent is charged with two counts of trafficking in a controlled drug contrary to s 32(3) of the Controlled Substances Act 1984 (SA) (‘the CSA’). Each count relates to drugs seized by police after they stopped a vehicle driven by the respondent. Police officers stopped the vehicle exercising the powers conferred by ss 47E and 40H of the Road Traffic Act 1961 (SA) (‘the RTA’). After stopping the vehicle and administering an alcotest to the respondent, police officers searched the vehicle driven by the respondent and his person and located methylamphetamine (the subject of Count 1) and 3,4‑methylenedioxyamphetamine (MDA) (the subject of Count 2).
Prior to trial, the respondent filed a Rule 39 application,[2] alleging the traffic stop was unlawful and seeking the exclusion of the impugned evidence under the public policy discretion. During a voir dire hearing, the prosecution called evidence from the two police officers involved in the traffic stop, namely Senior Constable Oakes (‘Oakes’) and his partner, Senior Constable Knott (‘Knott’). There were also a series of agreed facts relied on by the parties.[3]
[2] Interlocutory application filed 4 October 2024 on file DCCRM-24-009583.
[3] Exhibit VDP4.
On 15 April 2025, the Judge ordered that the evidence be excluded in the exercise of the public policy discretion.[4] The Judge ruled that the sole purpose of the police officers’ decision to stop the respondent’s vehicle was for the ‘ulterior purpose’ of investigating unlawful activity described in intelligence briefings (relating to drug activity) rather than to administer an alcotest, and this rendered the traffic stop unlawful.
[4] Bunning v Cross (1978) 141 CLR 54.
The Director complains that the Judge erred in her construction of the relevant statutory provisions, made erroneous factual findings and erred in the exercise of her discretion excluding the evidence.
On 5 June 2025, this Court granted the Director permission to appeal and allowed the appeal. The Court ordered that the Judge’s order excluding the evidence be set aside. The Rule 39 application dated 4 October 2024 was dismissed. The reasons for those orders follow.
The evidence
On 14 June 2023 at about 2:00pm, police officers Oakes and Knott were stationed at the Mount Barker Police Station. They were on uniform mobile patrol performing general duties together. Oakes was driving a marked police vehicle. They drove past an address on Faehrmann Avenue which was known to police as a ‘local drug address’. There, they observed a white Hyundai Getz in the driveway.
Oakes parked the police vehicle in a position near the premises to observe the white Hyundai Getz. He said that the vehicle had previously been seen at the respondent’s home address, and he was aware the respondent did not have a valid driver’s licence. Oakes was also aware of information from an intelligence briefing (received about a week earlier) that the respondent was ‘selling drugs and driving around in a little white Hyundai Getz.’ This provided a further link between the respondent and the white Hyundai Getz.
Oakes was asked why he stopped to observe the Hyundai Getz. He responded: ‘well just to see if, yeah, [the respondent] was driving it because we thought, yeah that would be - if we could get it and was driving then, yeah, we would just – getting a drive disqualified arrest probably wouldn’t take too long.’
At approximately 2:30pm, both police officers observed the Hyundai Getz reverse out of the driveway but neither saw who was driving the vehicle. Oakes said the Hyundai Getz drove a short distance, partly on the wrong side of the road, before turning right onto Victoria Road. In cross-examination, Oakes agreed that he decided to stop the Hyundai Getz before seeing this aberrant driving.
The police officers continued to follow the vehicle. A short time later, Oakes activated the emergency lights. The vehicle did not stop immediately; however, it slowed down. Oakes and Knott both observed the driver remove a strap from his right shoulder before placing something over the passenger’s front side area or near the centre console. They also observed there to be only one person (the driver) in the vehicle. The vehicle did not stop but was not moving quickly. The driver of the vehicle did not appear to be trying to evade police. The vehicle turned right onto Hughes Street where it finally stopped.
Oakes stated that the purpose for stopping the vehicle was to ‘identify the driver and conduct an alcotest.’ He said his power to do so was ‘I think the alcotest is the Road Traffic Act, I think s 47 something like that.’ He said he had no specific reason to conduct an alcotest and more specifically, ‘I didn’t have any suspicion that he was drink driving or anything.’
Before exiting the vehicle, Oakes activated his body-worn camera,[5] and retrieved the alcotest and a straw (used to administer an alcotest). He said a male exited the Hyundai Getz whom he immediately recognised as the respondent. Both Oakes and Knott said they have had dealings with the respondent in the past. The respondent approached the police and told them ‘…he did not have a licence or something along those lines.’ Oakes then directed the respondent to undertake an alcotest (which recorded a zero result). He also conducted a record of interview with the respondent during which the respondent was questioned about his driver’s licence.
[5] Exhibit VDP2.
Oakes and Knott searched the vehicle pursuant to s 52(9) of the CSA. Oakes said that by this stage, he had reasonable cause to suspect that the respondent had committed a drug offence based on the following matters: the intelligence briefing stating the respondent was selling drugs; $450 cash found on his person; and his observations of the respondent pulling something off his shoulder and placing it in, or near, the centre console. During the voir dire, and on appeal, the respondent did not challenge the legal basis for the search.
In cross-examination, Oakes confirmed that his purposes for stopping the vehicle was to conduct an alcotest and to identify the driver. He agreed that he did not mention that he wished to identify the driver in his statement but rather, said that he stopped the vehicle to conduct a ‘mobile driver test’. There was no clarification as to what he meant by the term ‘mobile driver test’.
It was suggested to Oakes that he stopped the vehicle because it was associated with the respondent, and it was seen leaving a ‘suspected drug linked address.’ Oakes responded, ‘(t)hat’s why we had stopped and watched the vehicle and waited for it to drive but we stopped the vehicle because it was driving, we didn’t know who was driving at the time.’ Oakes then gave the following evidence during cross-examination:
QBut in this instance, you were waiting for this particular vehicle to see if it left that address.
AThat’s correct.
QSo, you were using it as an investigative tool, the alcotest power.
AI guess to investigate who’s driving, yes.
…
QAnd then you’ve seen this car at this address which is also separately drug related, and it’s the combination of this car and this address that’s caused you to exercise your power to stop the car for an alcotest.
AYes.
QSo really you’re trying to figure out what’s going on and why this person, who this person is, why they’re at the address and what’s going on.
AWell, the first point is to stop and find out who the driver is and alcotest them and go from there.
…
Oakes agreed that he was not concerned that the driver of the Hyundai Getz was, or could have been, drink driving.
Knott also gave brief evidence. He agreed that Oakes was in control of the police vehicle, and he was the person who activated the lights to stop the Hyundai Getz. Knott said that he was not told why the vehicle was being stopped and it was not his decision to stop the vehicle. Knott said that when the vehicle stopped and the driver got out of the vehicle, he recognised him as the respondent, whom he believed did not hold a valid driver’s licence.
Parties’ submissions on the voir dire
Defence counsel sought exclusion of the evidence on the basis that Oakes had exercised his powers under ss 47E(2) and 40H of the RTA to stop the vehicle as an investigative tool for an ‘ulterior purpose’. That is, although there was a power to stop the vehicle for the purpose of requiring the driver to submit to an alcotest, this was not the purpose for which the police had, in fact, stopped the vehicle and thus their conduct was unlawful.
Defence counsel also submitted that the legislative intention for enacting s 47E of the RTA was to prevent persons from driving a vehicle whilst affected by alcohol. Yet, Oakes’ decision to administer the alcotest was not for that purpose but as a pretext to investigating suspected drug activity which was ulterior to the purpose of detecting and deterring drink driving, and for which the provision was enacted.
It was submitted that given the breadth of the power exercisable under s 47E, any misuse of it should not be condoned by the courts, and the evidence should be excluded in the exercise of the public policy discretion.
On the other hand, the prosecution submitted that Oakes’ purpose for stopping the vehicle was primarily to administer the alcotest. The fact that Oakes had another purpose to stop the vehicle, namely, to ascertain the identity of the driver, did not vitiate the validity of the exercise of the power under s 47E(2). The prosecution emphasised that the concession made by Oakes, that the stop was for an ‘investigative purpose’, was explicitly confined to ascertaining who was driving the vehicle.
The prosecution submitted that Oakes had the power to stop the vehicle for the purposes of directing the driver to produce a licence pursuant to s 40H of the RTA and s 96 of the Motor Vehicles Act 1959 (SA) (‘the MVA’) (‘a licence check’). It was submitted that while Oakes did not advert to s 96 of the MVA in his evidence, his misunderstanding as to a source of power to stop the vehicle did not render his actions unlawful.[6]
[6] R v Romeo (1982) 30 SASR 243.
Accordingly, the prosecution, in effect, contended that Oakes had more than one purpose for stopping the vehicle (that is, to ascertain the identity of the driver and to administer an alcotest) and there was a valid source of power to stop the vehicle for each of those purposes. There was no ‘collateral purpose’ or ‘ulterior purpose’ and Oakes’ conduct in stopping the vehicle was not unlawful.
In the alternative, the prosecution submitted that if the Judge held that traffic stop was unlawful, the evidence should not be excluded in the exercise of the discretion.
The Judge’s findings
After outlining the evidence and the parties’ submissions, the Judge made various findings which are now the subject of challenge in this Court.
The Judge found that when Oakes purportedly exercised the powers under ss 40H and 47E(2) of the RTA stating that he intended to conduct a mobile alcotest and identify the driver, his actual intention was ‘to see whether the driver was in fact the [respondent] and, if so, investigate whether he was involved in unlawful activity.’[7]
[7] R v Owens [2025] SADC 38 at [59].
The Judge said:[8]
…Senior Constable Oakes used the power he knew existed under s 40H and s 47E(2) to stop the vehicle but he did so for the sole purpose of investigating whether it was the [respondent] (who was known to him) who was driving and, if so, whether there was any evidence of the suspected unlawful activity with which the intelligence briefings had been concerned. The fact that an alcotest was performed does not alter that conclusion and nor does it ipso facto establish that the direction to stop was for that lawful purpose. The mere fact that an alcotest was actually conducted does not make the stopping of the vehicle lawful.
(Emphasis added).
[8] R v Owens [2025] SADC 38 at [62].
The Judge concluded that ‘this was not a random stop for the purposes of promoting road safety by alcotesting the driver’[9] and Oakes ‘would not have stopped this vehicle if he had not thought [the respondent] may have been driving it and [the respondent] may have been involved in unlawful activity.’[10]
[9] R v Owens [2025] SADC 38 at [63].
[10] R v Owens [2025] SADC 38 at [63].
The Judge was satisfied the direction to stop the vehicle was not made in the legitimate exercise of the powers conferred by ss 40H and 47E(2) of the RTA, noting that Oakes conceded that he was not concerned that the driver was, or could have been, drink driving.
In relation to the purported exercise of the powers under s 40H of the RTA and s 96 of the MVA, the Judge said:[11]
The first purpose of the direction to stop the vehicle was to see whether the driver was [the respondent] (but not by means of requesting him to produce a driver’s licence). The first purpose of the direction to stop was achieved as soon as [the respondent] stopped his vehicle, got out and was recognised by Senior Constable Oakes. At no stage did Senior Constable Oakes ask [the respondent] to produce a licence. On the contrary one of the first things he said to [the respondent] was that he knew that [the respondent] did not have a licence. Senior Constable Oakes conceded that he did not need to ‘check ID’.
[11] R v Owens [2025] SADC 38 at [66].
The Judge concluded that this was not a case of a police officer exercising a statutory power for a legitimate purpose while being alert to the detection of other potential offences or mindful of other police objectives. Rather, Oakes used the powers in ss 40H and 47E(2) of the RTA to stop a vehicle as an investigative tool (in relation to alleged drug activity) and this was ‘improper and in contravention of the law conferring that power.’[12] Her Honour considered that ‘the fact that an alcotest was administered was, in the circumstances of this case, completely ancillary and subsidiary to the purpose for which the vehicle was in fact stopped.’[13]
[12] R v Owens [2025] SADC 38 at [68].
[13] R v Owens [2025] SADC 38 at [69].
The Judge then returned to the question of whether Oakes’ purpose in stopping the vehicle was to request the driver to produce a licence to complete a ‘licence check’ thus exercising the powers under s 40H of the RTA and s 96 of the MVA, and the applicability of the principle in R v Romeo.[14] The Judge said:[15]
The evidence and factual findings I have made render the principle of no application. Senior Constable Oakes never said that the purpose (or one of the purposes) of the stop was to request the driver to produce a licence. I have found that his purpose was to identify whether it was [the respondent] who was the driver so he could then investigate the possibility that [the respondent] was engaged in unlawful activity. Further, Senior Constable Oakes said that [the respondent] did not have a licence. Accordingly, no ‘licence check’ could be or would need to be conducted if it was indeed [the respondent] who was driving. Senior Constable Oakes knew [the respondent] from previous dealings and was able to recognise him immediately.
This is not, in truth, a case about a mistake as to the source of authority pursuant to which an act is undertaken. Section 47E and s 40H RTA did, in their terms, authorise Senior Constable Oakes to stop the vehicle and conduct an alcotest. Senior Constable Oakes purported to invoke these sections, but he did so for an ulterior purpose.
Section 96 MVA cannot be relied upon as rendering the stop lawful because the purpose of stopping the vehicle was to see if [the respondent] was driving and investigate the possibility of criminal activity. On the factual findings I have made the purpose was not to conduct a licence check, and, in any event, invoking s 96 MVA for these purposes would also have been the use of a statutory power for an ulterior purpose.
[14] (1982) 30 SASR 243.
[15] R v Owens [2025] SADC 38 at [77]-[79].

The Judge also found that there was an insufficient basis for Oakes to form a reasonable suspicion under s 52(9) of the CSA and under s 68 of the Summary Offences Act1953 (SA) (‘the SOA’). Whilst the prosecution conceded that s 52 of the CSA could not be relied on, and her Honour so found, that issue was not raised on appeal, and we do not address whether that concession was properly made. As to s 68 of the SOA, this statutory power only permits a police officer to stop a vehicle where there they have reasonable cause to suspect the commission of an indictable offence. Neither the basic offence of driving while disqualified contrary to s 91(5)(a) of the MVA, nor the offence of driving without a valid licence contrary to s 74 of the MVA is an indictable offence.
The Judge held that the stopping of the respondent’s vehicle was unlawful.
The Judge then turned to consider the question of whether the impugned evidence should be excluded in the exercise of the public policy discretion. Her Honour found that the search was ‘irrevocably tainted by the initial illegality’ of the unlawful search and ‘the discharge of that duty requires the discretionary exclusion, in the public interest, of evidence obtained by unlawful conduct.’[16]
[16] R v Owens [2025] SADC at [98].
The Judge granted the application to exclude the evidence.
Appeal grounds
The Director seeks permission to appeal against the interlocutory decision on the following grounds:
1.The Judge erred in her construction of the powers contained in ss 40H and 47E(2) of the Road Traffic Act 1961 (SA) in finding that the stopping of the respondent’s vehicle was unlawful.
2.Further or in the alternative, the Judge erred in excluding the evidence in the exercise of the public policy discretion:
a. in particular, where on the Judge’s findings the officer held a genuine belief his actions were lawful, and where the powers were in fact exercised including in the uncontested application of the alcotest, on the basis that those powers were exercised in connection with investigation of the respondent, it was not open to exclude the evidence in the circumstances.
Ground 1
Under this appeal ground, the Director complains that the Judge misconstrued ss 47E(2) and 40H of the RTA, and further, reached her conclusion as to the unlawfulness of the police conduct in stopping the vehicle on the basis of erroneous factual findings.
Section 47E of the RTA provides:
47E—Police may require alcotest or breath analysis
(1) Subject to this Act, if a police officer (whether or not performing duties at or in connection with a driver testing station) believes on reasonable grounds that a person—
(a)is driving, or has driven, a motor vehicle; or
(b)is attempting, or has attempted, to put a motor vehicle in motion; or
(c)is acting, or has acted, as a qualified supervising driver for the holder of a permit or licence,
(d)the police officer may require the person to submit to an alcotest or a breath analysis, or both.
(2) A police officer may direct a person driving a motor vehicle to stop the vehicle and may give other reasonable directions for the purpose of making a requirement under this section that a person submit to an alcotest or a breath analysis.
Section 40H of the RTA states:
40H—Direction to stop vehicle to enable exercise of other powers
(1)   An authorised officer may, for the purpose of or in connection with exercising other powers under a road law, direct—
(a)the driver of a vehicle to stop the vehicle; or
(b)the driver of a vehicle or any other person not to do one or more of the following:
(i)move the vehicle;
(ii)interfere with it or any equipment in or on it;
(iii)interfere with its load.
(2)   A direction to stop a vehicle may require that it be stopped without delay, or that it be stopped at the nearest place for it to be safely stopped as indicated by the authorised officer.
(3)   A direction to stop the vehicle, or not to move it, or not to interfere with it or any equipment in or on it or with its load, does not prevent an authorised officer from giving the driver or another person any later inconsistent directions under a road law or any other law.
(4)   A direction ceases to be operative to the extent that an authorised officer—
(a)gives the driver or other person a later inconsistent direction; or
(b)indicates to the driver or other person that the direction is no longer operative.
(5)   A person commits an offence if—
(a)the person is subject to a direction under subsection (1); and
(b)the person engages in conduct that results in a contravention of the direction.
Maximum penalty: $5 000.
(6)   In this section—
stop a vehicle means to stop the vehicle and keep it stationary.
The Director also relies on the power conferred by s 96 of the MVA as a road law within the meaning of s 40H.
Section 96 of the MVA states:
96—Duty to produce licence or permit
(1) The driver of a motor vehicle, if requested by a police officer to produce the driver’s licence or learner's permit, must produce the licence or learner's permit either—
(a)forthwith to the police officer who made the request; or
(b)within 48 hours after the making of the request, at a police station conveniently located for the driver, specified by the police officer at the time of making the request.
Maximum penalty: $1 250.
Before turning to consider whether the Judge’s findings were erroneous, it is necessary to make some general observations about the operation of ss 47E and 40H of the RTA.
Section 47E(1) contains a power vested in a police officer to require a driver to submit to an alcotest if the police officer believes on reasonable grounds that the person is driving a motor vehicle. A police officer may require a person to undergo an alcotest on the sole basis that the person was driving the vehicle. It is evident from the terms of the provision that there is no requirement that the police officer has reasonable grounds to suspect that the driver was affected by drugs or alcohol. Nor is s 47E(1) confined by reference to a specific purpose. Rather, the power is conditional on a belief formed on reasonable grounds that a person is driving a motor vehicle.
Section 47E(2) provides that a police officer may direct a person driving a motor vehicle to stop a vehicle and may give other reasonable directions for the purpose of requiring a person submit to an alcotest or a breath analysis. The power to stop a vehicle under s 47E(2) is conferred for the specific purpose of requiring the driver of the vehicle to submit to an alcotest or breath analysis. Relevantly to the present case, whether the exercise of a power for more than one purpose gives rise to invalidity is a question of statutory construction.
In R v Kola,[17] (‘Kola’) the Court of Criminal Appeal considered the power to establish a breath testing station (‘BTS’) conferred by s 47DA of the RTA.[18] The appellant submitted that the BTS was not lawfully established because the primary purpose of the establishment of the BTS was to target vehicle related crime; and conducting alcotests was only a secondary purpose, as was the detection of other offences under the RTA. The Court of Criminal Appeal held that on the facts of that case the BTS was not established for the sole purpose of enabling alcotests to be conducted but rather that it was intended that the power ‘be used at a time and place that would facilitate the use of the BTS for the detection of other offences.’ Chief Justice Doyle (with whom Perry and Lander JJ agreed) said:[19]
As I have said, when a statutory power is conferred on a police officer, one would normally expect the power to be exercised along with such other powers as the police officer has. It seems to me that there is nothing offensive to the policy of the section, or to the protection of common law rights, if a BTS is set up in a manner that will facilitate the concurrent conducting of licence and vehicle safety checks for instance, as long as this is done while alcotests are conducted, and as long as drivers are not delayed except for the a1cotest. If one accepts that a police officer at a BTS is entitled to exercise available common law and statutory powers to deal with evidence of an offence which comes to the officer's attention at the BTS, or exercise powers which arise because of a suspicion formed while at the BTS, it seems to me unrealistic and artificial to say that those powers may be exercised, but that the establishment of the BTS is unlawful if the officer establishing the BTS intends that to occur and facilitates it occurring, as distinct from treating it as an incidental benefit should it happen. I also consider that it would be impractical to draw this distinction, when scrutinising the purpose of the person who established the BTS.
In other words, I consider that a BTS is established lawfully if established for the purpose of conducting alcotests, even though it is established at a time or place or in a manner (or all of them) which will facilitate the detection of other offences.
… there will be circumstances when an extraneous purpose is such that the establishment will not be lawful, even though alcotests are conducted. Drawing the line between those situations and what I regard as lawful may not always be easy.
… I emphasise that the establishment of the BTS was not a mere pretext upon which to stop vehicles for purposes other than conducting alcotests.
[17] (2002) 83 SASR 477.
[18] Section 47DA(1) of the RTA stated: ‘A breath testing station may be established by members of the police force at any time on or in the vicinity of any road for the purpose of enabling alcotests to be conducted in relation to persons driving motor vehicles on the road.’ The power to submit to an alcotest was than conferred by s 47E(2a) which stated: ‘A member of a police force may require the driver of a motor vehicle that approaches a breath testing station established pursuant to section 47DA to submit to an alcotest.’
[19] (2002) 83 SASR 477 at [42]-[43].
The Director contends that the reasoning in Kola is apposite when construing the power in s 47E of the RTA.
The terms of s 40H of the RTA authorise a police officer to direct a driver of a vehicle to stop for any purpose connected with a road law. Relevantly, the authorisation contained in s 40H(1)(a) of the RTA is expressly stated to be purposive and may be exercised for the purpose of, or in connection with exercising other powers under a road law.
In R v Neal,[20] (‘Neal’), the appellant submitted that the police officer stopped the vehicle pursuant to s 40H of the RTA and s 96 of the MVA for an improper purpose, namely, to harass the appellant. The police officer gave evidence that the vehicle was speeding, and denied that his prior dealings with the appellant played any significant part in his decision to pull over the vehicle. The trial judge rejected the proposition that the officer stopped the vehicle to harass the appellant and found that he did so because the vehicle was speeding and to conduct a licence check.
[20] [2017] SASCFC 44.
Chief Justice Kourakis (Nicholson and Parker JJ agreeing) referred to the findings of the primary judge and observed no reasons were given for those findings. The Chief Justice said:
However, it is not improper for a police officer to make a request of a person in circumstances in which a duty to comply with the request will arise, and at the same time be alert to other proper policing objectives. It is different if the power or authority is exercised for illegitimate reasons like personal vindictiveness, or in an attempt to obtain a personal benefit. The exercise of the power or authority for reasons of that kind is an abuse of the power and the conduct may be unlawful.
More difficult questions may arise in cases sometimes loosely described as police harassment. It is understandable that police resources will be focussed on persons and occasions where they are more likely to be effective. For those reasons, it is sometimes the case that police powers or authorities are properly enlivened, and exercised more frequently with respect to certain persons, or in certain kinds of circumstances where the persons being targeted may subjectively view that conduct as harassment. However, other than in the extreme cases of personal vindictiveness or benefit it is difficult to see how that conduct can be characterised as unlawful or improper.
The authority of Neal supports a construction of s 40H that authorises a police officer to direct a driver of a vehicle to stop the vehicle for any purpose connected with a road law even where that officer has a collateral motive to do so. There are, of course, limits such as in cases of personal vindictiveness or personal benefit.
In the present case, the Director contends that Oakes’ decision to stop the vehicle was for more than one purpose (to administer an alcotest and to identify the driver of the vehicle) and was a valid exercise of the powers conferred by ss 47E(2), and 40H of the RTA and s 96 of the MVA. It is in this context that the Director challenges the Judge’s findings as erroneous.
As outlined earlier, the Judge found that police officer Oakes exercised the powers conferred by ss 47E and 40H of the RTA for the sole purpose of investigating whether it was the respondent who was driving the vehicle and, if so, to substantiate the unlawful activity with which the intelligence briefings were concerned. Her Honour found, in effect, that Oakes’ decision to stop the vehicle for the purpose of administering an alcotest was a pretext to provide the police officers with an opportunity to investigate other suspected unlawful activity contained in the intelligence briefing. That unlawful activity related to selling drugs in the general area of Mount Barker.
In considering the Director’s challenge to this essential factual finding which underpinned the Judge’s reasons for excluding the impugned evidence, this Court is required to undertake its own assessment of the evidence. As the High Court explained in Fox v Percy:[21]
Within the constraints marked out by the nature of the appellate process, the appellate court is obliged to conduct a real review of the trial and, in cases where the trial was conducted before a judge sitting alone, of that judge's reasons. Appellate courts are not excused from the task of “weighing conflicting evidence and drawing [their] own inferences and conclusions, though [they] should always bear in mind that [they have] neither seen nor heard the witnesses, and should make due allowance in this respect”.[22] In Warren v Coombes,[23] the majority of this Court reiterated the rule that:
“[I]n general an appellate court is in as good a position as the trial judge to decide on the proper inference to be drawn from facts which are undisputed or which, having been disputed, are established by the findings of the trial judge. In deciding what is the proper inference to be drawn, the appellate court will give respect and weight to the conclusion of the trial judge but, once having reached its own conclusion, will not shrink from giving effect to it.”
As this Court there said, that approach was “not only sound in law, but beneficial in … operation”.[24]
(Footnotes in original).
[21] (2003) 214 CLR 118 at [25].
[22] Dearman v Dearman (1908) 7 CLR 549 at 564, citing The Glannibanta (1876) 1 PD 283 at 287.
[23] (1979) 142 CLR 531 at 551.
[24] Warren v Coombes (1979) 142 CLR 531 at 551. See also Taylor v Johnson (1983) 151 CLR 422 at 426; Jovanovic v Rossi (1985) 58 ALR 519 at 522; cf Moran v McMahon (1985) 3 NSWLR 700 at 715-716 per Priestley JA.
After reviewing the whole of the record, and bearing in mind those principles of appellate restraint, we consider that the Judge’s factual findings were erroneous for the following reasons.
First, Oakes gave evidence that he stopped the vehicle to administer an alcotest to the driver and to identify the driver. Immediately after stopping the vehicle, and consistent with his evidence as to his purpose for doing so, Oakes exited the police vehicle taking with him the alcotest items and a straw. It is of some significance that even after he became aware that the driver was, in fact, the respondent, he nonetheless proceeded to administer the alcotest. He also proceeded to question the respondent about his driver’s licence. Oakes’ actions upon exiting the vehicle strongly supported his evidence that his purpose for stopping the vehicle was, as he stated, to administer an alcotest.
Secondly, the Judge’s finding that the purported exercise of the powers under s 47E(2) was a mere pretext for an ‘ulterior’ purpose of investigating unlawful activity contained in the intelligence briefings (confined to selling drugs) ignored the evidence that Oakes believed that the respondent was driving while disqualified contrary to s 91(5) of the MVA, or in the words of Oakes, if it was the respondent driving, he would be ‘getting a drive disqualified arrest’. There was unchallenged evidence from both police officers that they believed the respondent was disqualified from driving or driving without a valid driver’s licence. The respondent also admitted that he did not have a valid driver’s licence. Oakes’ evidence that he stopped the vehicle to administer an alcotest and to identify the driver of the vehicle needs to be viewed in the broader context of the other unchallenged evidence, and the fact that after stopping the vehicle and recognising the respondent as the driver, the police officers proceeded to interview the respondent about his driver’s licence.
Moreover, under cross-examination, it was never suggested to Oakes that his reason for stopping the vehicle was for the sole purpose of investigating alleged drug activity, separate from investigating whether the respondent was driving disqualified or without a valid driver’s licence. It was never put to Oakes that he did not stop the vehicle to investigate one or other of those driving offences. Indeed, Oakes qualified his answer to the suggestion that he used his powers under s 47E and 40H to stop the vehicle as an ‘investigative tool’ by confining that concession to investigating the identity of the driver.
In short, the Judge’s finding that Oakes exercised the powers under ss 47E and 40H of the RTA for an ‘ulterior purpose’ ignored the evidence given that the respondent was driving while disqualified or without a valid licence and the police officers’ beliefs as to that matter.
In light of those matters, the Judge’s finding that Oakes’ sole purpose for stopping the vehicle was to see whether it was the respondent who was driving and, if so, investigate whether he was involved in unlawful activity with which the intelligence briefings had been concerned (which related to drug activity only) cannot be sustained.
Rather, upon our review of the whole of the record, we are satisfied that the evidence establishes that Oakes stopped the vehicle for the purposes of administering an alcotest and to ascertain the identity of the driver in the context of investigating whether the respondent was driving while disqualified contrary to s 91(5) of the MVA or driving without a valid licence contrary to s 74 of the MVA.
We are also satisfied, for the reasons which follow, that Oakes had the power to stop the vehicle to ascertain the identity of the driver, including whether it was, in fact, the respondent that was driving the vehicle pursuant to ss 40H of the RTA and s 96 of the MVA.
Section 40H of the RTA and s 96 of the MVA
Relevantly, as mentioned earlier, the power contained in s 40H(1)(a) may be exercised for the purpose of, or in connection with, exercising other powers under a road law. A road law is defined in s 5 of the RTA as meaning the RTA, the MVA, or rules or regulations under either of those Acts.

The purpose for which the power to stop contained in s 40H(1)(a) may be exercised is to be drawn from the content of a road law. Section 96 of the MVA is a road law within the meaning of s 40H of the RTA. When s 96 of the MVA is read together with s 40H(2)(b) and (c) of the RTA, it is evident that a police officer may direct the driver of a vehicle, that is on a road, to stop for the purpose of, or in connection with, requesting that the driver produce their licence or learner’s permit. Section 96 is plainly concerned with ensuring that the relevant driver is licensed to drive and is complying with any conditions of their licence.
At the time Oakes made the decision to stop the vehicle, he did not know whether the respondent was in fact the driver of the vehicle. Oakes stated that one of his purposes for stopping the vehicle was to ascertain the identity of the driver of the vehicle. As it turned out, it was in fact the respondent driving the vehicle and given he was known to both police officers, there was no need to check his licence to ascertain his identity. Contrary to the Judge’s reasons,[25] not asking for the respondent’s driver’s licence did not exclude that he stopped the vehicle for a licence check.
[25] R v Owens [2025] SADC at [77].
As mentioned earlier, it is to be accepted that Oakes did not, in his evidence, state that he was exercising the powers under s 40H of the RTA and s 96 of the MVA when he stopped the vehicle, nor advert to those powers. Nonetheless, it is well-established that a legislative power may be called in aid to support the lawfulness of a police officer’s actions even though the police officer did not intend to exercise that power or indeed, advert to its availability or purported use.[26]
[26] R v Romeo (1982) 30 SASR 243.
In summary, for the reasons given earlier, the Judge’s finding that Oakes exercised his power to stop the vehicle for the sole purpose of investigating whether the respondent was driving the vehicle, and if so, whether there was evidence to substantiate the unlawful activity with which the intelligence briefings were concerned, was erroneous.
Rather, we are satisfied that Oakes decided to stop the vehicle for two purposes: to administer an alcotest to the driver (which is precisely what he did); and to ascertain the identity of the driver by a licence check (which proved unnecessary).
In the circumstances of this case, and for the reasons outlined earlier, Oakes had the power to stop the vehicle pursuant to s 47E(2) of the RTA to administer an alcotest and under s 40H of the RTA and s 96 of the MVA to conduct a licence check to ascertain the identity of the driver. In regards to the latter source of power, Oakes’ failure to advert to s 96 did not invalidate the lawfulness of his conduct.
For those reasons, the Judge erred in finding that the stopping of the vehicle was unlawful.
There being no impropriety or unlawfulness, the public policy discretion was not enlivened. Accordingly, there is no need to consider Ground 2. Had it been necessary to do so, we consider the Judge was wrong in excluding the evidence given her finding that Oakes was genuine in his belief that he had the power to stop the vehicle, the respondent’s concession that the subsequent search was otherwise lawful, the cogency of the evidence and the seriousness of the offending.
Permission to appeal
This Court will only grant the Director permission to appeal if the Judge’s decision to exclude the evidence is an ‘interlocutory judgment’ and if satisfied of either of the two limbs of s 157(3) of the CPA. In the present matter, the Director relies on the first of the two limbs, namely that the Judge’s decision has destroyed or substantially weakened the Crown case and, if correct, is likely to lead to its abandonment.
We are satisfied that the Judge’s decision to exclude the evidence is an interlocutory judgment, as it was a decision made on a substantive question before a conclusion to the criminal proceedings.[27] It is also plain that the exclusion of the evidence has destroyed the prosecution case in respect of the two trafficking charges and, if correct, would lead to the abandonment of those charges. The case in respect to Count 1 is that the respondent trafficked 31.58 grams of methylamphetamine, and in respect to Count 2, it is alleged that he trafficked 9.29 grams of methylenedioxyamphetamine (MDA). Without the evidence of the seizure of the drugs, the prosecution will not have a case in respect of either count. This will inevitably result in the charges being abandoned.
[27] R v Marshall [2023] SASCA 105 at [98]-[133].
In considering whether to grant permission to appeal, we have had regard to the not insignificant quantity of drugs (particularly in respect of Count 1) and the relatively serious nature of the offence. We have also had regard to the fact the Judge’s findings were, for the reasons outlined earlier, plainly erroneous. While we have had regard to the principles of double jeopardy, the respondent is yet to have a trial and there is no significant delay in the matter proceeding to trial.
For those reasons, permission to appeal was granted and the appeal allowed. The Court ordered that the order excluding the evidence obtained as a result of the stopping and subsequent search of the vehicle and person be set aside. The Rule 39 application dated 4 October 2024 is dismissed.