Tolling a Statute of Limitations — a time period during which a statute of limitations for bringing a specific type of legal action is temporarily stopped from running.
Fraudulent concealment is a common law doctrine that may be invoked to toll a statute of limitations. Under this doctrine, if a defendant has concealed his misconduct, then the limitations period shall start from the point when the plaintiff discovers his claim, or should have discovered it with due diligence.
SO, IF THE IRS AND/OR FBI KNEW OF HUNTER'S CRIMES BUT BASICALLY CONCEALED THEM, THAT SHOULD BE 'FRAUDULENT CONCEALMENT' AND THUS 'TOLL' THE STATUTE OF LIMITATIONS.....