CONCORD, N.H. (AP) – The father of a missing Massachusetts college student was at the New Hampshire Supreme Court on Tuesday seeking police records and evidence in her disappearance.

Maura Murray, 21, was last seen shortly after crashing her car in a snowbank off Route 112 in Haverhill on Feb. 9, 2004.

That was nearly three years ago, and her father, Fred Murray, of Weymouth, Mass., said he is frustrated at the apparent lack of progress in the police investigation – and the state’s refusal to share any information with him or private investigators.

“I’m a little angry that it has to come to this, that you have a missing persons case that can remain under investigation for 50 years,” he said before the hearing. “It’s absolute stonewalling.”

Murray’s lawyer, Timothy Ervin, argued that while exemptions to the state Right-to-Know Law and the federal Freedom of Information Act allow police to withhold evidence in open investigations, they cannot withhold all 2,500 records indefinitely. He asked that a judge review the records to determine whether some should be released.

“The court has to make a specific showing that disclosure would interfere with the ongoing investigation,” he said.

Senior Assistant Attorney General Nancy Smith argued the records, including witness interviews, phone records and police reports, could become critical evidence in a criminal prosecution.

“We empathize and sympathize with Mr. Murray’s concern over the disappearance of his daughter,” she said.

But she warned the justices that if they grant the elder Murray’s request, anyone – including the perpetrator of a crime – could seek the release of investigators’ files before a suspect has been charged.

That argument persuaded a lower court judge, who ruled in September that releasing the files could result in destruction of evidence and witness intimidation.

But the justices questioned Smith sharply, asking why the state couldn’t even say whether Murray’s disappearance is being treated as a missing persons case or a criminal matter. Smith said investigators cannot rule out the possibility Murray left the accident scene on her own.

“We don’t have a body. … We do have information we are pursuing that this may involve a crime,” she said.

Chief Justice John Broderick questioned whether judges and the public should be required to accept assurances by police and prosecutors that every record in an investigation is exempt from access laws, no matter how old the case.

“If that’s enough, then you can never penetrate that wall,” he said.

But Broderick also suggested the legal system could be overwhelmed if prosecutors must prepare comprehensive indexes of every record for judges to review, or if judges must review the actual documents.

“So a trial judge would be required – in addition to everything else they do every day – to go through cartons and cartons of documents?” he asked Ervin.

Justices did not indicate when they would rule on the matter.