MasterChef Finalist Josh Marks -- Doctors Evaluating Him for Mental Illness

MasterChef finalist Josh Marks wasn't in his right mind during a bizarre, violent encounter with University of Chicago cops this week -- so says Josh's lawyer, who tells TMZ, doctors are currently evaluating him to determine whether he's suffering from a mental illness.

Josh's attorney Lisa Marie Butler tells us, “We are working closely with medical professionals to determine if Josh's behavior could be related to mental health symptoms."

She adds, "The Josh that you are hearing about in police reports this morning is not the spirited Gentle Giant that we know.”

As we reported, 26-year-old 7-foot-2 Marks was arrested by University of Chicago police Monday after allegedly punching a cop and trying to grab his gun. 3 officers tried to subdue Marks with batons and pepper spray, but he broke free and took off running.

It eventually took 5 officers to chase him down and handcuff him. Once in custody, cops claim Marks blamed Gordon Ramsay for his outburst, claiming the celeb chef had possessed him and turned him into God. We're told there was no evidence of drug use.

Multiple sources close to Marks believe he suffers from bipolar disorder. Fellow "MasterChef" contestant Tali Clavijo tells us, "Josh was two different people ... He seemed to always be a party guy, but he had this other side trying to be good." He added, "He had split personalities."