With mental health concerns being revealed in the history of 22-year-old Jared Lee Loughner, who's accused in the shooting of a congresswoman woman and several others in Arizona, 7NEWS wanted to know why a person with mental health issues could buy a gun.Loughner is accused of shooting Rep. Gabrielle Giffords, D-Arizona, at a grocery store gathering on Saturday. Six people were killed and 14 injured.7NEWS discovered that the background check gun buyers in Colorado must go through searches the person's criminal and court record. The Colorado Bureau of Investigation looks for past felonies, warrants, restraining orders and court findings for mental deficiency.Not all states have denials in place for mental deficiency, according to the CBI.The CBI said even a person who makes questionable mental health statements or admits to being seen by a medical professional for mental health issues, they could legally buy a gun as long as a court has not deemed that person "mentally deficient.""Someone who's seeking mental help from a medical professional but who has not committed a crime, can they purchase a gun?" asked 7NEWS reporter Marshall Zelinger."Basically, yes. It's only a court that makes that designation," said CBI spokesman Lance Clem."The system allows for persons that are mentally defective to not be able to buy guns, but that has to be adjudicated," said gun dealer David Peterson, owner of The Shootist Pistol Range. "If I feel that they are unstable or they're going to commit suicide with the gun, I have the ability to refuse to sell them the gun."If a gun dealer does prevent someone from buying a weapon based on their own concern, there's no system in place to warn other dealers of that concern."They can always contact (the Bureau of Alcohol, Tobacco, Firearms and Explosives) and through various channels," said Clem."There is no network in place to contact other gun dealers," said Peterson. "There are enough gun stores in the Denver metro area that I can't make 1,500 phone calls to alert everybody. I could probably go to the ATF and make that statement, and they would probably follow up on it, but it probably wouldn't be in time to get them to not buy the gun."7NEWS met with Rep. Diana DeGette, D-Colorado, and asked her if she thought someone's mental health medical records should be considered before a gun purchase is allowed."Yes, I think somebody's mental health history does need to be taken into account, but secondly, we need to make sure we have strong databases," said DeGette."We know that our records are pretty up-to-date. We know that the system works pretty well. There are mistakes that get made every once in a while, but generally speaking, I think we've got a good system. It's about as good as you can get," said Clem."Why is pretty well, good enough?" asked Zelinger of the CBI's record-keeping system."You can never guarantee 100 percent that the wrong people have access to firearms because, one way or another, they may get them."Gun owners 7NEWS spoke with would rather not be in the business of evaluating customers."It's not my business whether or not they are mentally deficient or not; that falls back to the Colorado Bureau of Investigation," said Peterson. "I want to be able to say, 'It's the Colorado Bureau of Investigation says that you can't buy a gun, not me.'""As inviting as it may be to blame individuals with mental illnesses for violence, this does a grave injustice to most of the people with serious mental illness who live in our communities and who pose no threat to themselves or others," said Laurie Elliott, clinical director for Arapahoe/Douglas Mental Health Network.According to Elliott, 1 in 4 people have a mental health illness, such as depression or attention deficit disorder. She said people would be unfairly disqualified if mental health medical history determined gun ownership qualifications.