ST. PETERSBURG — Police say Bradley Bolden is a gang member who committed a brazen crime: using a .45-caliber handgun to shoot and kill private security officer Matthew F. Little at a St. Petersburg apartment complex last year.But at the moment, the murder case hinges not on DNA evidence or eyewitnesses, but on subtle interpretations about Bolden's brain.Attorneys are debating whether Bolden, 21, may be too mentally retarded to understand the murder case against him.A psychiatrist and a licensed clinical psychologist have evaluated Bolden, and a court hearing is set for today.Attorneys from the Pinellas-Pasco Public Defender's Office are expected to argue that Bolden cannot understand some of the basics of a criminal trial. That's significant because courts have held that defendants cannot get a fair trial unless they are mentally capable of understanding their rights, and able to participate in important decisions such as whether to testify.Prosecutors don't deny Bolden may be mildly mentally retarded, but say it's not so severe he should be considered incompetent.The experts who spoke in pretrial interviews with attorneys agreed that Bolden is mentally slow, with an IQ at one point measured at 62. But they differ on other aspects.Psychologist Daniel Patz spoke to Bolden and said he seems aware that he has an attorney helping him, but "he says he doesn't know the term state attorney, or prosecuting attorney, or the role." He recommended Bolden receive what is known as "competency training" to teach him some of the issues he will need to understand about being a criminal defendant."A lot of these things he sort of half gets it, then loses it, and then it falls apart," Patz said.But psychiatrist Dr. Emily Lazarou found "partial malingering" in Bolden. In other words, she said, he might be acting more mentally retarded than he is."He knows he's slow, so he knows that he can act slow on other things," which sometimes in the past might have gotten him out of things he didn't want to do, she said.Lazarou said Bolden does at times appear confused in talking about the case. But instead of attributing this to his mental retardation, she considered it more "because he doesn't know if he says something, what the repercussions of what he says would be in the street setting, to himself, or his family."If the judge agrees with the defense attorneys who say Bolden isn't mentally competent, it doesn't mean he avoids prosecution. But it would delay a trial.In this case, Bolden could be sent to a state hospital for the competency training designed to make him sufficiently aware of legal issues. Then there would be further evaluation to see when the prosecution could move forward.The victim of the May 2011 shooting, Little, was 26 and about to be married. He had made plans to become a Hillsborough County sheriff's deputy.At the time, he worked for a security firm and typically worked in Tampa, but had been assigned this night to the Mariner's Pointe apartments in St. Petersburg, in the Pinellas Point area. It's an area that has suffered from gang activity and other crimes.St. Petersburg police officers went to the complex at 1:14 a.m. after someone complained of gunshots. They found nothing, but later returned after Little failed to check in with his supervisors. He was found dead by the pool and tennis courts.No motive was revealed by authorities, although they said Bolden did make a comment that he didn't like police or security officers.Curtis Krueger can be reached at [email protected] or (727) 893-8232. Follow him on Twitter at @ckruegertimes.