An acting New York State Supreme Court justice ruled that a second grand jury called to investigate so-called subway vigilante Bernard H. Goetz, who shot four youths last December, could continue its deliberations. In a court hearing, Goetz's lawyers sought to have the grand jury dismissed. Justice Stephen G. Crane did not require Dist. Atty. Robert M. Morgenthau to produce new evidence in open court, ruling that "the defense's claim lacks merit."