Criminal Law Questions? Ask a Criminal Lawyer.
If the evidence that was used was procured by or through mail fraud, then that evidence could be tainted. The opposing party could file a motion for a new trial or rehearing if this is discovered after the case that was won by the government worker was completed. This would be considered new evidence (this being the mail fraud) and could be grounds for a new trial.
The answer to your question is not a definite YES, the evidence will be thrown out. However, it is grounds to look at it anew and potentially throw it out or weigh it differently in coming to a conclusion.
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