CHESAPEAKE, Va. - Consumed with righting racial inequality and injustice, sniper suspect Lee Boyd Malvo became yesterday the latest young defendant to use the film The Matrix as part of an insanity defense to explain killings that seem to have no clear explanation. The 1999 film has been used, with some success, in at least three other murder cases in which young defendants attempted to justify their crimes with allusions to the movie's philosophy that the world people live in is only a dream sequence controlled by a computer. Violence is condoned as a way to get out of the...