STEPHEN Flynn had a challenging task as he rose to his feet in the Commons this afternoon for his first PMQs as Westminster group leader. His predecessors had time to settle into their role before facing the heightened atmosphere of question time, but Flynn was thrown in at the deep end, squaring up to Rishi Sunak just hours after his election as leader.

Last night he said that he wanted to show the Prime Minister that the SNP “mean business”, yet actually demonstrating this is always tricky for third parties in British politics.

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The SNP have one overriding disadvantage as a parliamentary group at Westminster. It is not their internal politics or their policy priorities, but their party size and the position in the parliamentary pecking order which this brings. In the House of Commons, party group size is everything.

The chamber and its procedures were designed for two main political parties. Erskine May, the book of parliamentary procedure, writes that the presence of a third main party “complicates” but does not destroy the broad principle. This is evident in the design of the chamber, with Flynn speaking today not from a despatch box opposite the Prime Minister but from a seat off to his right. His predecessors quickly learnt that a seat towards the centre of the chamber was the best choice for commanding attention of the House, but it does not bring the same gravitas as is afforded to Keir Starmer.

The National: As SNP group leader, Stephen Flynn has to speak from the side of the Commons chamber at PMQsAs SNP group leader, Stephen Flynn has to speak from the side of the Commons chamber at PMQs (Image: Westminster TV/PA)

It is also reflected in the parliamentary rights on offer for political parties. And these rights really matter. They govern the speaking, membership and business opportunities available for opposition parties, a system in which the Official Opposition will always take the spoils. They are the reason why the SNP leader will always be making contributions to debates after Keir Starmer’s points have already been hammered home.

Flynn will need to over prepare each Wednesday, pre-empting the topics Starmer will be leading on and adapting quickly to the tone of proceedings if his planned questions become redundant or seem out of kilter.

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His performance today was an assured one. His relaxed stance and assertive questioning displayed no hint of any nerves. He spoke to the whole House, not just to the Prime Minister. And importantly for him, the House listened.

There was far less of the heckling which coincided with Ian Blackford’s first PMQs performance – one in which the Speaker had to intervene to ask government MPs to be quiet.

Going forwards though, Flynn will need to work hard to offset the disparity between himself and Starmer and to ensure that the SNP voice is heard. He needs to make the group visible and find ways to show that they can punch above their weight.

Both Angus Robertson and Blackford had an acute awareness of how to strategically use parliamentary procedure to their advantage, capitalising on it repeatedly to give the party extra airtime.

We saw evidence of this last month when the SNP dominated the Order Paper at PMQs on the day of the Supreme Court’s referendum judgment. We saw it when Blackford used one of the group’s three opposition day debates to censure Boris Johnson following the release of the Sue Gray report. And we saw it during the scrutiny of Brexit legislation when the group used interventions to overwhelm the committee stage of the EU (Notification of Withdrawal) Bill with SNP voices.

Flynn will need to use these strategies too if he is to ensure that the party continues to punch above its weight in the House of Commons.

Dr Louise Thompson is a senior lecturer in politics at the University of Manchester