I've seen a lot of material on this theory, but have yet to see anybody cite this good piece of evidence.
"The Gungan General" is the twelfth episode in Season One of theStar Wars: The Clone Wars television series.
Commander Stone sends Jar Jar to "negotiate", knowing that the Gungan's ineptitude will be useful. As the pirates take him hostage, Jar Jar accidentally rams one tank into another and subsequently shuts down the power grid. The Weequays attempt to kill him, only for the clones to hold them at gunpoint.http://starwars.wikia.com/wiki/The_Gungan_General
Jar Jars supposed bumbling antics in this episode is also arguably responsible for the death of the Senator that puts Binks in charge of the Clones Troopers.