There was a 'don't employ illegal migrant workers' commercial.
The scenario is that someone is going to get a builder to do something, but when the builder comes to the door he is turned away 'because he has been all over the paper' i.e. fined for employing illegal migrant workers.
1. This is at the same level of plausibility as the 'don't fare dodge or your colleagues will shun you' ads they used to have on the tube. Clearly this is absolute toss, people might think you are a cheap bastard but the dominant response will be 'bad luck, old bean'. At some point the tube realised this and went for a come on we need the money approach 'London depends on the system that depends on your fare', which seems far more plausible and likely to work to me.
2. Notice that it is a builder. It's those working classes we have decided to target and intimidate. Not an accountant, solicitor or gasp horror ad agency employing illegal cleaners, because they are People Like Us. (Also, of course, they will be doing the employing at one level of remove. No, no, no, we didn't wonder how they could do it so cheaply, we thought they must be efficient and streamlined).
3. Why this? Not really just intimidating the working class, but Sending A Message. We are on the case. Well then, why not 'Are you an M.P.? Putting your kids on the books whilst having them do no bloody work at all? Then you could get a smack on the wrist, and your party leader might withdraw your whip, so for God's sake employ one of your chums' children and get him to employ yours and no-one will think anything of it.' Or 'Are you the CEO of a major national mortage bank? If you have a completely ludicrous and unsustainable business model, this, allied with crap and hysterical media reporting will lead to an unphotogenic run on the bank, leading a 10th rate Prime Minister to bankrupt the fucking country. So don't do it, OK?'
I have not been so sodding furious listening to the radio for a long time.