Lord Patten told a Public Accounts Committee that they would need to speak to the previous Director General Mark Thompson when he was questioned about payoffs.
Referring to his own lack of knowledge over the payments in July, Lord Patten told MPs: "If you call a previous director general of the BBC I will be as interested as you are why we didn't know."
At the time Mr Thompson claimed that the BBC Trust was aware of the scale of hefty pay-offs made to former staff.
The BBC's head of HR, Lucy Adams, has admitted making a mistake in her evidence to a committee of MPs investigating excessive payoffs.
A spat has broken out between ex-BBC chief Mark Thompson and the Trust over large payoffs to departing staff.