Lie detecting pants of doom!

I have a new idea that I hope would reform the justice system. I'm not sure why we don't use lie detectors in court, surely that would save a lot of money as there would be no need for any of the court staff we currently have. I went on jury service last year and the whole thing seemed a big waste of money. Are silly wigs really nessisary? So more use of the lie detector was the basic idea but then I took that one step further to invent the 'Lie detecting pants of doom' which would be pants that the defendant would have to where and if they lied the clever lie detecting pants would set on fire. just a little painful spark for a small crime, but proper flames for more serious offences. I think it would significantly reduce the amount of people who lie in court.

The job of the jury would be a lot easier, they wouldn't have to make any decisions, all they would have to do is shout 'liar liar pant on fire!' and I personally think people would do jury service voluntarily if they got to see criminals with their pants on fire. so this would save even more public money. I think if I put this idea forward to the government they would eventually accept it. Some weirdo in the oldern days got them to wear silly wigs and they still do that now, surely my idea is more sensible than that.