多年以来,众议院建立了一系列的规矩,包括在辩论时,不能指控总统“撒谎”。
http://news.yahoo.com/s/ap/20090915/ap_on_go_co/us_health_care_heckling
A House Rules Committee summary of guidelines for members states that while it is permissible to challenge the president on matters of policy during debate, personal attacks are off limits. House rules note that a member could refer to a presidential message as a "disgrace to the nation" but it would be impermissible to call the president a "liar," a "hypocrite" or say he was "giving aid and comfort to the enemy."