Who was the killer in Basic Instinct 2?

In a scene or 2 before Nick's partner gets killed, when Nick is at Katherine's home and she tells him she doesn't want to see him anymore, she is printing out here story for her new book. The camera shows what is on the paper and it describes the scene of Nick's partner's death in the elevator. Therefore, it would seem that Katherine was the killer because she wrote about it in her book and printed it out before it happened.