The fruit of the poisoned tree according to Halacha

There is a consideration here of future prevention versus current punishment. Perhaps it is right to accept the evidence and punish the person who committed the offense. This way, both deterrence and justice are achieved. In terms of halakhah, I do not know of a clear reference to the matter, and certainly not a sweeping one. There are tangential cases such as the case of a person who forged a bill in order to create evidence of fraud) in 2:33. Or the case of a forger in Gittin 4:1, regarding a forger from within it, and the comment of Reka there. There are of course all kinds of evidence that is indirectly invalid due to offenses such as the testimony of a wicked person, but there it is not the invalidation of the evidence but of the person. This is not the case with every offense either.