The usual rule in the AAT (and other merit review tribunals) is that the law in force at the time of the tribunal’s decision is applied. This can give rise to some to some difficult issues if there has been a change in the law in between when the application is lodged and when the case is decided. For example I have recently had a case where a change to the skilled occupation list (by imposing a caveat that couldn’t be met) affected my client unfairly.
There is a general presumption (both at common law and in the Legislation Act) that laws can’t act retrospectively if there is an effect on accrued rights. The law is clear that making an application for review in the AAT does give rise to an accrued right to have the application determined in accordance with the law existing at that time (see for example Esber v Commonwealth (1992) 174 CLR 430 at 440-441). So far, so good for my clients – they have an accrued right.
However, there is an exception to that general proposition if there is a clear statutory intention to the contrary. In the context of the Migration Act one of the drafting mechanisms often used to show such an intention is the phrase “not finally determined”. This is actually a defined term in section 5(9) of the Migration Act as follows:
For the purposes of this Act, an application under this Act is finally determined when either:
(a)a decision that has been made in respect of the application is not, or is no longer, subject to any form of review under Part 5 or 7; or
(b)a decision that has been made in respect of the application was subject to some form of review under Part 5 or 7, but the period within which such a review could be instituted has ended without a review having been instituted as prescribed.
The effect of “not finally determined” when it appears, is evidence of a statutory intention for the law in force at the time of the review to apply. The “unfair” (but not illegal) consequences are apparent from a number of cases including Kaur v Minister for Immigration and Border Protection  FCA 168; Turkish Kebab & Pizza Shop v Minister for Home Affairs  FCCA 188; and Su v Minister for Immigration and Border Protection  FCCA 1629.
Careful consideration needs to be given to the wording of transitional provisions in these types of cases.