SANTA FE — Repeat domestic violence offenders would face tougher, mandatory penalties under legislation unanimously approved by the House on Thursday. The measure would require a minimum of 48 hours in jail for a second conviction, 30 days for a third, and six months for a fourth or subsequent conviction, which would be a felony. An offender with repeat convictions also would be required to participate in a domestic violence treatment program. A similar measure passed the House last year but died in the Senate. Rep. Mimi Stewart, D-Albuquerque, said tougher penalties are needed because domestic violence is a serious crime. “New Mexico is the third highest in domestic violence homicides. This is a growing problem,” said Stewart. The bill, which is part of Gov. Bill Richardson’s legislative agenda, goes to the Senate. The House also approved a measure that allows domestic violence victims to obtain a substitute mailing address so they can’t be tracked down by those who battered them. The secretary of state’s office would serve as the mailing address and the office would forward mail to the domestic violence victim.