Venezuela's top court on Monday struck down an amnesty law approved last month by the opposition-dominated Congress, scuttling an effort by critics of President Nicolas Maduro to secure the release of jailed opposition activists. The supreme court's constitutional chamber ruled that the law violated constitutional principles because it promoted impunity and offered amnesty for crimes that were not eligible for such treatment. "This impunity law cannot pass," said Maduro, who had vowed to veto it, in a televised broadcast minutes before the court's decision was released.