A play on words that seem to be referring to the dictator Mao Zedong (Tse-tung) as being a law-abiding citizen, when in fact the phrase refers to LOFLMAO, a variation of ROFLMAO, meaning LOL'ing on the floor laughing. Despite the inherent redundancy, this phrase has been slowly growing in use as internet chat rooms seek newer ways to express themselves.
chadbrochillz18: I thought the new Twilight
movie was pretty good.
chadbrochillz18: Yah, Rob Pat is on top of his game. As was Shark Boy.
PeteZombie: GTFO. NOW.
bloodninja2: Lawful Mao
PeteZombie: You too.