When Dr. Apgar was killed in an explosion aboard the station, Commander Riker was accused of the murder. Tayna's depositions were used to create the holoprograms Tayna Simulation Three and Tayna Simulation Four, in which she stated that Riker and Manua Apgar were about to have an affair and when Dr. Apgar caught them, Riker threatened the doctor. She also said that the doctor was in fear of his life and when she wanted to contact the authorities, he told her he would take care of Riker.
Riker was cleared of the crime when it was proven that Dr. Apgar had developed a weapon which he was going to sell to the highest bidder, and tried to kill Riker so he would not find out. (TNG: "A Matter of Perspective")