Former Western Australian treasurer Ben Wyatt (AAP Image/Richard Wainwright)

The appointment of former Western Australian Labor treasurer Ben Wyatt to the Rio Tinto and Woodside boards last week is at one level a great development because he is the first Indigenous director of any major Australian public company.

However, from a governance point of view, there really should be a cooling-off period before former politicians can be paid by corporate entities they used to regulate or tax -- or under-tax, in the case of Wyatt and Rio Tinto.

Wyatt is the cousin of federal Liberal MP Ken Wyatt and retired from the WA parliament after a 15-year career at the state election in March.