Here’s the defense: I was there with the on-location drug dealer, and I’m a myopic, drunken Mongoloid.

It was throw-everything-at-the-wall time yesterday in closing arguments for the Brooklyn mechanic accused of swiping a $2,000 Balenciaga purse from Kirsten Dunst after sneaking into a 2007 Soho Grand hotel movie shoot. So far, it seems to be working.

Convicted shoplifter, gun toter and car thief James Jimenez has given a Manhattan jury so much to think of that it’ll be back today for a second day of deliberating his claim that he’s too dumb to be a burglar.

He had permission to be at the shoot, he insists, because his friend was invited — to “deliver” drugs to the penthouse green room used by Dunst and British actor Simon Pegg.

That, plus the fact that, in his lawyer’s words, he’s just stupid and didn’t even know he was at a hotel.

“I thought it was just a building,” he said. “I don’t know.”