ATLANTA – More than half the states are not complying with a post-Virginia Tech law that requires them to share the names of mentally ill people with the national background-check system to prevent them from buying guns, an Associated Press review has found.

The deadline for complying with the three-year-old law was last month. But nine states haven’t supplied any names to the database. Seventeen others, including Maine, have sent in fewer than 25, meaning gun dealers around the U.S. could be running names of would-be buyers against a woefully incomplete list.

Officials blame privacy laws, antiquated record-keeping and a severe lack of funding for the gap the AP found through public records requests.

Eleven states have provided more than 1,000 records apiece to the federal database, yet gun-control groups have estimated more than 1 million files are missing nationwide.

Maine adopted a law in 2007 that directs the State Bureau of Identification to provide some mental health records to the National Instant Criminal Background Check System. Records provided involve people who have been involuntarily committed after a comprehensive hearing process, such as when a hospital obtains a court order forcing someone to remain in the hospital.

The states that have failed to submit any mental health records are: Alaska, Delaware, Idaho, Massachusetts, Minnesota, New Mexico, Pennsylvania, Rhode Island and South Dakota.