Uruguay's Senate, in a last-minute bid to avert a showdown with the armed forces, approved a bill barring court action against most officers accused of violating human rights. The measure was sent to the House of Deputies, where a brawl broke out during debate. President Julio Sanguinetti was awaiting the bill's approval so he could sign it into law before a court hearing today for an officer charged with kidnaping. The bill would bar prosecution of military and police officials accused of human rights abuses that occurred before March, 1985. Tens of thousands of suspected leftists were jailed under military rule in the 1970s.