Rep. Austin J. Murphy (D-Pa.) said yesterday that he never allowed anyone to cast House votes in his name and maintained that the House ethics committee has yet to produce an alleged "secret accuser" to testify against him.

Murphy also said he has not decided whether to seek reelection next year.

He spoke to reporters as he and his attorneys entered a closed committee hearing on allegations that he had an unidentified colleague vote in his name in the House twice in 1978 and once in 1982.

Murphy referred to a "secret accuser" in news accounts who had raised the "phantom voting" issue. Murphy said newspaper reports had said "that a former staffer would swear under oath, and so far they {the committee} have failed to produce any person who swears under oath to the voting irregularities."

Yesterday's testimony centered on allegations that Murphy permitted congressional resources including furniture and photocopy services to be diverted to his former law firm in Charleroi, Pa. The law firm is in a building adjoining Murphy's congressional district office. He sold his interest in the firm in 1977.

Murphy also faces allegations that he placed an associate on a House subcommittee payroll and that the employe became a "no show" after four or five months.