Lawyers for the clerk of the U.S. House of Representatives filed new reasons in federal court today to keep a Glen Burnie insurance agent from getting internal documents from a House committee, thus at least temporarily staving off a contempt-of-court order against the clerk.

Attorneys contended that insurance agent George H. Benford, who has filed a $25 million lawsuit against ABC-TV and employes of the House Select Committee on Aging, is not entitled to investigative files of the committee because they are privileged documents protected by the "speech or debate" clause of the Constitution. Also, they argued, documents in the Capitol in Washington are outside the jursidiction of the federal court in Maryland. House Clerk Benjamin J. Guthrie has been ordered by a House resolution not to comply with any court-ordered subpoena for the documents and has no choice but to obey the House.

Benford, an independent agent for the American Family Life Assurance Co. of Columbus, Ga., contends he was surreptitiously filmed trying to sell cancer insurance to two committee workers posing as prospective buyers.

Parts of the film were aired on the ABC Nightly News program in 1979. Benford said the filming violated Maryland eavesdropping laws and ruined his career.

The filming was part of a House committee investigation into the cancer insurance industry and was triggered by allegations that some companies were pressuring elderly people to buy insurance they do not need.

U.S. District Court Senior Judge Edward S. Northrop here ordered the House clerk held in contempt on June 24 when he refused to surrender House committee documents demanded by Benford. He ordered the clerk to pay a $500-a-day fine, but said he would delay the penalty to give Guthrie time either to comply, appeal the contempt order or present more specific reasons for resisting the subpoena.