Mee arrested Gibson for driving under the influence and wrote in his report the actor-filmmaker made anti-Semitic statements during the incident. Gibson subsequently apologized for his behavior.
Mee and his lawyer, Richard Shinee, told TMZ Wednesday the sheriff's department is firing the deputy because Sheriff Lee Baca believes Mee leaked Gibson's arrest report to the celebrity news Web site after he was instructed not to.
Department spokesman Steve Whitmore told TMZ the decision to terminate Mee was "not connected to the Mel Gibson arrest at all."
"We disagree with the characterization ... this was not retaliation," Whitmore said.
TMZ said Mee was officially told he is being fired because he allegedly violated procedure by engaging in a high-speed pursuit that ended in a fiery explosion last year, and then lied about the incident to his superiors.
Shinee said these are "trumped-up charges calculated to vindicate their wrath against him."
A hearing regarding the matter is scheduled for Thursday, TMZ said.