Chapel Hill, N.C. — The head of the state NAACP chapter said Monday that he wants a panel studying hate crimes on University of North Carolina campuses to recommend a specific policy for how to investigate such crimes.

At a meeting of the UNC Study Commission to Review Student Codes of Conduct as They Relate to Hate Crimes, Rev. William Barber said he also supports diversity training and changes in curriculum.

"What we need is a clear policy on how we investigate, a clear policy on what the penalties are, and we need a clear curriculum that truly teaches us more about how we must interface and be one community," Barber said.

The commission, which includes students, staff and faculty from 10 UNC campuses, is looking into whether the 16-campus UNC system should adopt a policy on the matter in the wake of four North Carolina State University students' spray-painting racist graffiti in the campus' Free Expression Tunnel the night after President Barack Obama was elected.

Barber, president of the state chapter of the National Association for the Advancement of Colored People, called for the students to be expelled, but N.C. State officials said they had no grounds to do that.

Barber said the message painted in the tunnel was specific in context of historical threats made against blacks.

"This language that has deep historical roots in 'terroristic' history is not free speech," Barber said.

Wake County's district attorney said the messages did not warrant a hate crime charge, and some groups, such as the American Civil Liberties Union, argue that the speech is protected under the First Amendment.

At a public-input meeting earlier this month, most in attendance supported the idea of a hate-crimes policy. But the majority of the dozens of e-mails sent to the commission in recent weeks have opposed it.

The commission, which is studying similar policies in other states, including Texas, California and Minnesota, is expected to make a recommendation to UNC President Erskine Bowles by the end of March.