Mel Gibson Back in Criminal Court ... As a Juror!!!

Mel Gibson has returned to criminal court today ... but this time he'll be the one passing judgment ... as a prospective juror!!!

A TMZ producer ran into Mel outside the jury assembly room. He's in the hallway reading a script, occasionally jumping on the cell phone talking business.

Mel was also chatting up some of the women in the hallway and even took some photos with them.

Mel is wearing a baseball cap, a dark sport coat, button-up shirt and jeans.

Mel is not being treated differently ... he's doing what all prospective jurors do -- wait.