Harvard has not yet decided how to respond to a written request from an attorney representing rapper Dr. Dre and rock group Metallica urging university officials to prevent students from accessing the music sharing program Napster.

University Attorney Allan A. Ryan Jr. confirmed Friday that the General Counsel's office had received the letter, sent to University President Neil L. Rudenstine.

The letter requests a reply by September 22.

Unlike similar efforts last spring to restrict student access to Napster at Yale and other schools, the letter to Rudenstine makes no explicit threat of legal action.

Instead, it posits that Harvard "has a moral, ethical and legal obligation" to prevent copyright infringement over its networks.

"I believe that you can easily recognize the irony of encouraging your students to matriculate in the creative arts, while engaging in behavior which, if unchecked, will make it impossible for those students to earn an income from their future creative efforts," wrote Howard E. King, the attorney.

Ryan told the Crimson last spring that he did not think the University would ban Napster traffic.

"I don't think there's an obligation to prevent our users from accessing protected material over the Internet," Ryan said.