The National:

LAST time we checked in with the BBC over its Motherwell Question Time, they confirmed only that an investigation was "under way".

That was in response to our queries about Billy Mitchell, AKA the "orange jacket man" and former Ukip candidate who has appeared a whopping four times as an audience member (speaking on three of those appearances), and the unrepresentative audience.

READ MORE: Question Time faces furious backlash over audience bias

So, while we eagerly await the results of that investigation, we thought we'd do a little research for ourselves – and the BBC are welcome to use the findings.

We went back to Stirling in 2013 – the first of the four times he popped up on our screens – and tallied up the appearance figures since then for all the guests on Question Time

What we found is, sadly, unsurprising.

The hardcore Unionist has appeared on the show more than almost every SNP politician. Below, in brackets, we've included the number of appearances they've made.

Mitchell has been on the show more than Keith Brown (1), Mike Russell (1), Joanna Cherry (3) and Ian Blackford (3).

He has been invited on to perform his Unionist rant more times than the BBC have invited Kate Forbes (1) and Stewart McDonald (1) ... and Jeane Freeman (1), Stephen Gethins (1), Pete Wishart (1), Hannah Bardell (2) and Kirsty Blackman (2).

Other politicians the Question Time selectors seem to think less worthy of the speaking time are Stewart Hosie (1), Tommy Sheppard (1) and Fiona Hyslop (2).

First Minister Nicola Sturgeon has been on three times.

Which SNP politicians have been on more than Mitchell, then? Alex Salmond, with eight – followed by Angus Robertson and John Swinney with six each.

And ... no other SNP politician has been on more than Mitchell.

Humza Yousaf and Tasmina Ahmed-Sheikh, with four appearances each, have only the same amount as Mitchell.

For some added context, Ruth Davidson and Kezia Dugdale have both been on the Question Time panel seven times.

Though, admittedly Mitchell still trails well behind his fellow Ukippers. Paul Nuttall has been on 10 times and Nigel Farage 11.

Choosing the audience, Question Time holds repeat appearances against its audience. With its panellists, it seems to quite like repeat appearances.

It makes the facts above even more damning.