Paying tax in and of itself is never illegal. Paying more tax than you owe is not illegal either. As far as taxes go, the only illegal thing is “not guessing the number right” and flat out refusing to pay.

Obtaining money through criminal activity is a crime, but that's a different crime that does not have anything to do with paying taxes.

It is a crime to knowingly accept money obtained through illicit activity, but guess what – the prosecutor for that crime is the government itself! You can't sue the government for unwillingness to prosecute.