Mike Pezzullo home affairs Paladin Manus Island scandal
Secretary of the Home Affairs Department Mike Pezzullo (Image: AAP/Lukas Coch)

Home Affairs secretary Mike Pezzullo and the bureaucrats responsible for administering Australia's offshore detention regime would have been hoping yesterday's defence of the Paladin contract at Senate estimates would have been enough to ward off the stench of scandal.

Instead, more questions have arisen about a department that seems unwilling to accept that there are any problems around its at-best slipshod approach to huge contracts.