Published: Dec 14, 2011 11:11 PM EST
Updated: Dec 14, 2011 11:31 PM EST

FORT MYERS, Fla.- Andrew Castor is accused of killing his 19-year-old neighbor in 2008 by stabbing her to death. WINK News obtained video showing him just moments after the allaged murder. But neighbors told us it wasn't the first sign of violence.

Aurea Moldonaldo says Castor fed her family cat to an alligator years before the murder. Now mental health experts are evaluating Castor to see if he knew the difference between right and wrong at the time of the murder. Castor's lawyer says atleast one doctor agrees that he could have been insane.