Presidents in Brazil have significant lawmaking powers, exercised either by proposing laws to the National Congress or by using (provisional measures), an instrument with the force of law that the president can enact in cases of urgency and necessity except to make changes to some areas of law (provisional measures cannot be used to change criminal law or electoral law). A provisional measure comes into effect immediately, before Congress votes on it, and remains in force for up to 60 days unless Congress votes to rescind it. The 60-day period can be extended once, up to 120 days. If Congress, on the other hand, votes to approve the provisional measure, it becomes an actual law, with changes decided by the legislative branch. The provisional measure expires at the end of the 60-day period (or the 120-day, in the case of extension), or sooner, if rejected by one of the Houses of Congress.