In this case, criminal proceedings were brought against defendant but he filed a motion to suppress the evidence gathered from his apartment by Drug Enforcement Agency Task Force Agent Taylor. The district court denied the motion to suppress, finding that Agent Taylor’s failure to review the warrant before executing it was a “simple mistake” that conferred no benefit on the Government and amounted at most to negligence. The judgment of the district court is affirmed, where: 1) the parties agree that the evidence was seized from defendant’s apartment in violation of the Fourth Amendment; but 2) Agent Taylor was not sufficiently culpable for the costs of suppression to outweigh its benefits, so the exclusionary rule does not require suppression in this case.