John Clifford's trial opened Monday in Manhattan. He's charged with misdemeanor assault and harassment in the March 2007 dispute.
Clifford has acquired a reputation as a self-appointed etiquette enforcer on the commuter railroad. He maintains he had a right to tell off the cell-phone chatterer, and he says the woman he slapped hit him first.
The woman testified that Clifford's antics "violated (her) space."
