no one granted him the power of god to take her life. she was slowly poisoned to death. probably one of the most hideous things that you can do to someone. this wasn't done in a moment of passion or anger of picking up a weapon that was handy to him. this was done with slow premeditation and over a period of time, and it's a hideous, hideous way to murder somebody. >> richard lyon insisted he had nothing to do with the poisoning death of his wife, nancy. as proof, he offered a receipt for arsenic that he said nancy had signed. prosecutors asked forensic experts whether this was, in fact, nancy's signature. >> i wasn't able to reach a conclusion as to authorship.