A federal court may award sanctions using civil procedures only if the sanctions are compensatory in nature, recompensing the harmed party for harm that was caused by (would not have occurred but for) the sanctioned party’s sanctionable conduct. For any sanctions beyond that or having a punitive or deterrent purpose, the court must employ criminal type of procedure with an independent prosecutor, full notice and hearing, jury trial, unanimous verdict etc. Furthermore, to award sanctions under its inherent power, whether compensatory or punitive, the court must find either: (1) a willful violation of a court order; or (2) bad faith. Here, the district court awarded a series of sanctions against plaintiff for sampling materials in the defendant school district’s buildings for testing for PCB contamination, the subject matter of the suit. An evidence sanction was reversed insofar as it barred admission of pre-suit sampling since that could not have violated any court order and there was no showing of bad faith. A sanction to pay for repair of the tested buildings was also reversed as to buildings damaged by pre-suit testing for the same reason. An attorney fee award to the defendant for bringing the sanctions motion was reversed insofar as the fees were incurred in seeking punitive sanctions. And the order denying plaintiffs statutory attorney fees as a sanction was also reversed. However, the order’s prospective prohibition of further testing was affirmed.