Question Time begins with a showdown between Minister and ... Minister?

A routine patsy question about the recently signed India Free Trade Agreement (FTA) turned into a Question Time rarity; a government minister being pressed not by the opposition, but by one of their own cabinet colleagues.

This has now happened twice in a week.

Question Time is a regular fixture of Parliament's sitting day agenda, known for its quips and potential gotcha moments. It is probably the most adversarial regular aspect of the House, when the government-versus-opposition dynamic, integral to the Westminster system, is most visible.

Twelve starter questions are available to non-ministerial MPs, allocated proportionally. On paper, this allows MPs from all parties to publicly quiz ministers on how they're doing their job. In practice, governing party MPs typically use their allocation of questions to ask friendly (patsy) questions, giving ministers an opportunity to talk positively about their work, like a parliamentary alley-oop.

Opposition MPs, on the other hand, use their questions to point out where they think the government is getting it wrong.

For instance, Tuesday's Question Time began with a standard patsy from National MP Tom Rutherford to Nicola Willis (in her role as minister for Economic Growth). Rutherford asked what recent announcement the government had made on economic growth, serving up Willis the chance to promote the newly signed FTA with India and outline the benefits for exporters and regional economies, including Rutherford's Bay of Plenty electorate.

National's play here was familiar, and reminiscent of the electorate-heavy days of first past the post: different regional MPs get a follow-up patsy each, and ministers offer locally-directed messaging.

Throughout this term, coalition party leaders David Seymour (ACT) and Winston Peters (New Zealand First) have often lent ministers - especially the prime minister - a helping hand with patsy questions, teeing up an easy answer after a difficult opposition question.

But for the second time in a week, Peters' supplementary to a cabinet colleague was not a softball question. Peters diverged from the usual script and pressed Willis on how the deal had been communicated to domestic audiences in India. The underlying message being that the FTA was more to India's advantage than New Zealand's.

Peters is well within his rights.

Question Time is supposed to be when MPs, even government MPs, hold ministers to account, even if they sit around the same Cabinet table.

New Zealand First is its own party, and while the coalition agreement includes "prioritising" FTAs, including with India; it does not mandate support for them. The traditional expectation of collective cabinet responsibility is not concrete in most coalition agreements, which allow parties to 'agree to disagree' on matters not nailed down in the agreement.

Nevertheless, it is rare for coalition disagreement to be demonstrated in Question Time.

Thus far this term, coalition tensions have been kept low key, or otherwise articulated in the media.

Peters also used Question Time to press the government on this issue, with Minister for Trade Todd McClay last week.

One could argue that it's healthy to have government MPs briefly setting aside coalition loyalties to hold colleagues to account, or that this is simply a coalition party trying to distinguish itself from its partners as the election looms closer. Either way, we may see more of it before Parliament rises for the election.

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