WASHINGTON -- A vote in the House of Representatives this week to punish Mexico for failing to extradite the suspected killers of Los Angeles County Sheriff's Deputy David March and other law-enforcement officers divided Southland lawmakers, though not entirely along partisan lines. Sponsored by two Colorado legislators, the amendment threatens to cut off aid to any country that refuses to extradite suspects in the killings of U.S. law officers. It would affect about $66 million in aid to Mexico, which has blocked the extradition of suspects who face either death penalty or life imprisonment sentences. It passed 327 to 98....