Legislation passed after the 2007 Virginia Tech shooting was supposed to ensure that people with a record of severe mental illness couldn't purchase guns. But many states are not submitting the requested information.

Anybody who has been involuntarily committed or been ruled mentally incompetent by a court is banned from buying a gun and should be listed in the national background check database. But the Virginia Tech shooter's name wasn't. The tragedy showed that mental health records in the National Instant Criminal Background Check system, NICS, are spotty.

A 2008 federal law promised to support states in their efforts to fill in the holes on the list. Over $1 billion were supposed to be given out. John Strong oversees the NICS system at the FBI, he said the money was meant to fund changes states needed to make within their systems, to provide the FBI with better records. More information, said Strong, would make the checks quicker and more accurate.

So far, only a fraction of the money has been distributed, and many states, including Pennsylvania, have submitted no records at all. Pennsylvania officials would not respond in an interview, but in a prepared statement said that quote "Long standing technical and legal issues remain to be resolved."

Max Nacheman is director of Ceasefire PA, he says the lack of record-sharing weakens the entire gun safety system: "The state police in their annual firearms report say that they have 500,000 mental health records in their data base that they search in Pennsylvania. But in the federal database there is not a single file from PA when it comes to mental health records. That means if one of those people goes to another state or moves to another state none of that data is available."

New legislation has now been introduced in Congress that would withhold grants from states that don't share mental health records.