COLUMBUS — — The system for keeping guns out of the hands of mentally unstable people is imperfect, according to Toby Hoover of the Ohio Coalition Against Gun Violence.

Most states, including Ohio, don't supply mental health info to federal authorities who run instant background checks on gun buyers. And buyers can avoid checks entirely by making purchases at gun shows.

When it comes to getting a permit to carry a concealed weapon, Ohio had not been checking a database of 12,000 people who have been adjudicated as mentally incompetent, Attorney General Marc Dann said.

Former AG Jim Petro disagrees, saying the database was built specifically so thorough background checks could be done on applicants for concealed-carry permits. The database did not include fingerprints, used as identifiers in criminal checks, so it wasn't considered entirely reliable, Petro said. It goes back only to 2004 and does not include anyone who voluntarily committed themselves to a mental institution, Hoover noted.

Dann said his office ran the 12,000 names against the 100,000 concealed-weapons permit holders and found two got permits before they were ruled mentally incompetent and two others were issued permits that are no longer active.

Dann promised his office would share the database of mentally incompetent people with the FBI, which conducts about 8 million annual background checks of potential gun buyers.

Federal law prohibits several categories of people from owning firearms, including felons, drug addicts, wanted persons and anyone adjudicated as mentally defective.