Instead, Sinodinos has opted for a half-way house by standing aside while the Independent Commission Against Corruption investigates his role as chairman of the subject company, Australian Water Holdings. He wants to return to the Abbott frontbench and the PM has given him every reason to think he can.

Under pressure: Senator Arthur Sinodinos. Credit:Andrew Meares

In a straight comparison, the O'Farrell and Sinodinos cases seem in different leagues. O'Farrell, clearly one of the best premiers NSW has produced for a long time and a standout among his contemporaries, has quit because he received a bottle of wine from someone trying to duchess him, and then apparently forgot about it. It is not as trivial as it sounds, but it is not Watergate either. I'll return to this directly.

Sinodinos, by contrast, was chairman of a company partly, if secretly, owned by the notorious Obeid family, and which was corruptly seeking to secure a lucrative public contract from the state government – a contract which, according to the ICAC counsel, Geoffrey Watson, SC, would have netted Sinodinos himself a multimillion-dollar pay day.

Moreover, Sinodinos was an AWH director and then chairman at a time when that near insolvent company was falsely charging Sydney Water for its own expenses, and was making multi-thousand dollar donations to the NSW division of the Liberal Party. The public is being asked to take on trust the claim that Sinodinos knew nothing about making the donations in one guise, nor receiving them in another.