Given that, if it was not raised in caucus perhaps Martin should have raised it herself to ensure it would not become a stumbling block later.
The second consistency is that for the second time, Justice Minister Andrew Little is the one to suffer from the mercurial ways of NZ First.
The first was when Little was given an assurance NZ First would not block his plans to repeal the "three strikes" legislation for repeat offenders, only for the wider caucus to subsequently decide to block it after all.
Tracey Martin was acutely aware of that example.
Some months ago she told the Herald it was because of that she was being very careful to take abortion reforms back to caucus before giving sign-off.
When push comes to shove, NZ First's desire for a referendum should have no real impact on the reform.
Little was negotiating with NZ First because he needed Cabinet sign-off to get the legislation before Parliament.
He got that.
Now MPs will vote and that Cabinet sign-off does not preclude NZ First MPs voting for or against that legislation as every other MP can.
To get a referendum now, NZ First's only option is to put up an amendment to the bill to try to have a referendum included.
Peters enjoys nothing better than creating a bit of suspense so left it a day to confirm NZ First would do just that.
It is unlikely to get support for that. National Party leader Simon Bridges has said he would not support it. Labour MPs will be fuming and there are already two referendums on the cards for the election. The Labour Party will not want a third.
Given that and the failure to raise a referendum during negotiations for the bill, NZ First could simply be posturing to allow Peters to say the party had tried to stick to its policy but was thwarted by others.
It remains unclear how NZ First MPs will treat the vote – whether its MPs will cast conscience votes in the usual sense, or whether it will follow the same path it did on euthanasia.
That was to agree to support the legislation but only if a public referendum was held before it came into effect.
This has also sparked a wider debate about what issues should rightly be decided by referendum.
National's Amy Adams has been most forthright on this, saying NZ First's desire to shunt such issues away to decision-by-referendum is cowardly and an abdication of responsibility.
Adams is right.
Referendums are a powerful tool for the public to force change Parliamentarians are dragging their heels on. They are essential for measures such as changes to electoral systems, where politicians have a vested interest.
But they should not be used by politicians as a means of dodging accountability for making those decisions.
There is a distinct whiff of NZ First trying to avoid having to pick a side on euthanasia and abortion by making their votes conditional on a referendum, rather than on "conscience".
NZ First MPs will not be alone in that sentiment. The lobbying on both sides of the debate is intense and can be abusive.
MPs are already sharing screenshots of their inboxes full of the results of coordinated abortion-related emails, an influx that can actually be counter-productive.
But that is what democracy entails.
Peters will have to wear that along with the rest of them.
In the end, the main damage wrought by NZ First's approach is the impression it gives of bad faith dealings. It has done little to endear NZ First to its coalition partner, Labour.
Andrew Little in particular will be left ruefully reflecting on the statement: fool me once, shame on you. Fool me twice, shame on me.
