you remember this form, sir, that you filled out and signed in front of kathleen williams?ing doing it? i don't know. i don't deny doing it. i just don't remember this form. >> i'll never forget as long as i live, he looked at the bottom on the last page and he says, but that's my signature. >> he had a devastating credibility problem. he couldn't keep his story straight on the witness stand. >> what was it like on the stand in those moments? >> it was a battle. i think, you know, i got a little cocky. i have nothing to hide. of course, lorena does. >> i think that's for this jury to decide, mr. bobbitt. >> i didn't know how to explain it, and i was frustrated. i didn't know how to explain the story. >> with a steady stream of witnesses testifying today that john bobbitt has a history of violent behavior, it may appear that he is the one on trial. >> her face was swollen. >> he was hitting her, punching her. >> so grabbed her hair like this and pulled her downward. >> they brought in dozens of witnesses to talk about the violence that she had experienced. >> i saw a bruise