A high school student who was jailed after he was accused of insulting President Recep Tayyip Erdogan was released from custody on Friday after his arrest caused an uproar. The 16-year-old boy was arrested this week after being accused of calling Mr. Erdogan a thief at a student rally. Opposition parties denounced it as the latest example of the government’s descent toward authoritarianism and its crackdown on free speech and dissent. It is a crime in Turkey to insult the president, and others have been arrested on such charges before, but it was the first time a minor has been detained. Dozens of lawyers volunteered to defend the teenager and petitioned for his release. The Justice Ministry will have to decide whether to allow the case to go forward.