A proposal that reinstates Utah’s use of firing squads to carry out executions narrowly passed a crucial vote Friday in the state’s Legislature after three missing lawmakers were summoned to break a tie. The Republican-controlled House voted 39 to 34 to approve the measure, sending it to an uncertain fate in the Senate, which is also controlled by Republicans. Senate leaders have declined to say if they will support it, and Gov. Gary Herbert, a Republican, will not say if he will sign it. The Senate president, Wayne Niederhauser, noted that no senator had stepped up to sponsor the measure, which could allow it to quietly fail. The House initially voted 35 to 35 on the proposal Friday morning. But Representative Paul Ray, who sponsored the measure, asked for three missing lawmakers to be summoned to the floor, where they all voted in favor. One other lawmaker switched to vote in favor. Mr. Ray has argued that trained marksmen would be faster and more humane than the drawn-out deaths that have occurred in botched lethal injections. His bill would call for a firing squad if Utah cannot get lethal injection drugs 30 days before an execution. Lawmakers voted in 2004 to stop allowing prisoners to choose death by firing squad. Some inmates were sentenced before the law changed and were given the option of going before a firing squad. It was last used in 2010 when Ronnie Lee Gardner was executed by five police officers with Winchester rifles.