The attorney representing a white former San Francisco Bay Area rapid transit officer convicted of fatally shooting an unarmed black passenger is asking a Los Angeles judge for a new trial.

Lawyer Michael Rains said in a 134-page filing Friday that Johannes Mehserle's (yoh-HAH'-nes MEZ'-ur-leez) involuntary manslaughter conviction should be overturned because jurors didn't hear a similar case involving a Kentucky officer who mistook his handgun for a stun gun.

Rains also says Los Angeles County Superior Court Judge Robert Perry erred in his jury instructions and that Mehserle's gun enhancement conviction should be overturned.

A jury convicted Mehserle in July in the 2009 New Year's Day shooting death of Oscar Grant on an Oakland train platform.

His trial was moved to Los Angeles amid concerns about whether an impartial jury could be found in Alameda County.