When an idea or something else is so stupid, that it drops to the level of Jar JarBinks. Props be deserved if you have the cojones to actually say it though.
Writer: Ok.. So we get Will Smith and his son... And they crash on an alien planet with fake british accents... And this planet tries to kill them.... But that planet is actually Earth!
Logical person: *Thinks* More like Jar Jar!
Had logical person been brave, this world would have been spared another atrocity.
Another example:
Writer: So it's a remake of Annie... BUT SHE"S NOT A GINGER!
Everyone: *Thinks* More like Jar Jar!
Guy: *Says* More like Jar Jar! that is a horrible idea. Just keep annie on broadway!
Everyone: That's Racist!
The moral being "Speak up if it's clearly a bad idea!"
A Rofl Jar Jar occurs when you jizz all over a poster of Chewbacca strictly for the lulz. The poster is preferably made by a fat ginger CA, or someone else that no one likes, and the result is a major hallocaust.