What a difference a lie makes. We appear to have a new type of lie. A lie to the media is certainly not a crime but it now seems to be – for those who deem themselves to be above the masses – not a real lie and not a problem either.

A lie to the media is just one of the PR options to be deployed when it seems like the best tactic. Not really an issue, say sorry if you are caught out but that's not a big deal because saying sorry is just another wheeze to use when your PR advisers say it would look good. You don't have to actually be sorry.

Sometimes contrition is the right look, at other times aggressive defence. If you are not telling the truth but that cannot actually be proved then saying "I can't recall" 50 times is another choice. Sometimes tears work a treat too. All just more arrows in the quiver of deception deployed by politicians and their ilk.

Except that this nonsense doesn't really wash with the public. We can feel the lie, smell it, see it in their eyes. We are not fooled and we don’t like it. Those who are supposed to serve us take us for idiots. They degrade themselves and politics and our country. They decrease our interest in the democratic process and corrode our faith in our leaders.

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Beyond the general impact their lying has on how we feel about those who govern us, the individual who lies tends not to grasp the effect of their little lie on our view of them as an individual. Once the lie is out there, especially if it sees the light of day despite efforts to keep it from public view, then what else the liar says are we to believe?

Let's take Tory life peer Michelle Mone first. She has now admitted on TV for all of us to see that she lied about her links to a company which supplied PPE for use in the UK during the Covid pandemic. That linkage was previously denied for some years. The contract to supply the PPE seems to have been a good one for the company, netting many millions of pounds profit. For our health service not so much, they are pursuing the supplier because they say the goods were defective. Baroness Mone denies this.

Whatever one thinks of the morality of what Michelle Mone did, she has crossed a simple and clear line, she is now a self-admitted liar. Once that line is crossed everything else comes into question.

Are her claims that she acted properly as a member of the House of Lords in this matter true? Has she genuinely not financially benefited at all from the PPE contract up to now? Did the profit from the contract really not allow Ms Mone or her husband to buy luxury playthings such as yachts and planes? Was Michelle Mone actually ever a highly successful entrepreneur?

The Herald: Michael MathesonMichael Matheson (Image: free)

The benefit of the doubt when it come to the answers to these questions has gone. To prove that someone is a liar is often difficult but to prove you are telling the truth when you are a proven liar is harder still. Acting honestly and honourably is central to being a member of the House of Lords. I hope we will not see Michelle Mone in Ermine again.

Michael Matheson, still Secretary for NHS Recovery, Health and Social Care in the already discredited SNP government of Scotland, has lied too.

He told the press when asked if there had been personal use of his iPad when he was on holiday in Morocco that there had not been. That was not a true statement and he knew it at the time. With much emotion and the heart-warming or sickening – take your pick – claim that it was to protect his children, he later admitted that wasn't true. He still insists that he did not lie to journalists about his £11,000 data roaming bill but I think we all know he sought to mislead the press and indirectly us by telling a lie.

So what are we now to make of the fact that he was originally content for the public purse to pay a large part of the bill for the use of his iPad on holiday? Was it true that at the time he thought he had spent so much time on purely parliamentary business that this must have been the cause of the massive bill, wrong SIM card or not? Was his expenses claim knowingly false or not?

Does his claim that his children only admitted weeks after the matter was in the public domain that it was they who had used the iPad to watch Celtic football matches sound plausible? Are we to believe that despite being a fan of Celtic and on holiday his children watched the footie but not him?

We do not know the answers to these questions but now that we know Michael Matheson lied what are we supposed to think?

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Michael Matheson should resign or be dismissed, it really is that simple. Keeping his head down and hoping it will blow over is wrong. For Yousaf to allow that is weak.

But I hear you cry, what about Boris Johnson, he misled people too. That's actually the whole point. Boris has left office but Matheson clings on.