The appellant made no complaint whatever against the bank until it refused to honour a cheque which in its view there were no funds to meet. He then issued his writ on 21st August 1931.
Upon these facts the appellant's case appears quite hopeless, When at the end of September 1930 he learnt that money had been drawn out of his account as on his behalf but not in conformity with his actual authority, he might have been at liberty to disown the drawings. But it must have been apparent to him that the bank had been acting and was continuing to act upon the assumption that, although the drawings were irregular in form, it might safely allow them. He was not at liberty to acquiesce in the assumption, watch his son continue the practice and then, when his son could get no further advantage from it, to depart from the assumption and SO obtain immunity, if not enrichment, at the expense of the bank.
Departure from an assumption upon which another person has acted to his detriment is not permitted to a party who, knowing or believing the other labours under a mistake in adopting it, has refrained from correcting him when it was his duty to do SO (Cf. Thompson v. Palmer 1 ).
In the present case, the conduct of the appellant goes much further. He stood by deliberately. He indorsed promissory notes which did not bear his wife's signature, intending them to be debited to the account in exoneration of his own liability on them. He knew and approved of the arrangement to close off the old overdrawn account and pay by monthly instalments out of the No. 2 account the liability arising from the drawings that he now repudiates. These facts are much stronger than those held to be sufficient in Greenwood V. Martins Bank Ltd. 2.
For the appellant it was contended that the respondent bank laboured under no mistake of fact, under none upon which it acted to its detriment, under none to which the appellant's silence con- tributed and under none which it was incumbent upon the appellant to correct.
The mistake lay in supposing that his son's cheques might be properly or safely paid out of the account. It might not have been
1(1933) 49 C.L.R. 507, at p. 547.
2(1933) A.C. 51.