Craig Fiato, a government informant called by the defense, testified alongside his brother Larry to impeach Detective Vannatter's credibility on a critical point: whether Simpson was considered a suspect when detectives first arrived at his Rockingham estate. Their testimony, combined with that of FBI agent Michael Wacks, contradicted Vannatter's sworn claim that Simpson was not a suspect at that time — dealing what was characterized as a serious blow to the prosecution's credibility on the question of police procedure and motive for the warrantless entry.