All weekend, Act supporters and friends of the Act Epsom MP were saying John Banks would "do the right thing".

That was code for saying he would resign, but nobody on his side would utter the words lest it looked like pressure.

Banks was determined to make the decision himself and to be seen to be making the decision.

If there was too much pressure, it could have caused him to hang on. The only parties to have benefited from that would have been Opposition ones.

Advertisement

It was clearly not obvious to Banks on the day the verdict was handed down that he had to resign from Parliament altogether.

Otherwise he would have had a plan and done so immediately, as he had in December.

At that time, he had decided that if he were committed for trial - on charges of making a false election donations declaration - he would step down as Act leader and announce his retirement from politics at the next election.

He was committed for trial and he duly resigned. It was well thought through and executed.

Not so for the verdict.

The fact that he did not have a plan ready last Thursday suggests he quite reasonably had prepared for only two possibilities: acquittal, or being forced out of his seat that day with a conviction.

The decision by the judge to delay a ruling on any conviction until sentencing on August 1 took everybody by surprise and complicated Banks' options.

The House is due to rise in July, before a possible conviction is entered.

Banks took advice on Friday about whether Parliament could forgo a byelection in Epsom in the eventuality of a vacancy. The answer was that Parliament would have to be recalled.

It may have taken the weekend for Banks to get over the shock of the verdict but his resignation was the only sensible option.

It means he will inflict less damage on his present party Act and his old party National to retain the Government benches.

And it should not affect his bid to clear his name. That could come either through a discharge without conviction or through an appeal against conviction if sufficient grounds are found for a challenge.

Act and Banks have had a respectful but not close relationship since Banks inherited the leadership in 2011 as sole Act MP.

If nothing else, Banks' decision to resign next Friday will preserve a modicum of respect. For a politician who has lost so much, that may count for a lot.