DEMONSTRATIONS and threats forced Haiti's legislature to hastily adjourn Tuesday before lawmakers could vote to censure the government of President Jean-Bertrand Aristide.Mr. Aristide's supporters set a building on fire, wrecked a political headquarters, and attacked two legislators. No serious injuries were reported. The fledgling legislature had called Aristide appointee Prime Minister Rene Preval for questioning and possible censure due to some opposition to the new government. But protesters chanted, "Don't lay a finger on Preval. You will get burned," as they set tires aflame. Radio and television stations relayed appeals from militant grass-roots groups for a big pro-government rally outside parliament during the censure debate. Shots were fired outside the headquarters of the leading political party. One legislator was slapped as he boarded a taxi, and another's home was stoned. Offices of two unions critical of Aristide's administration were ransacked and one was set on fire. If the legislative body had passed a censure motion, it would have necessitated appointment of a new Cabinet requiring legislative approval. Aristide, a popular left-leaning Roman Catholic priest who easily won election in December, Monday reaffirmed support for Mr. Preval. Aristide said the Cabinet's overthrow "could do much harm to major [international] negotiations," apparently referring to talks with foreign agencies about aid for his Caribbean nation.