A Los Angeles federal judge refused to order the arrest of a material witness in the Richard W. Miller spy case but warned government prosecutors that they should make sure that the witness is available to testify in Miller's espionage trial. The ruling was made by U.S. District Judge David V. Kenyon Jr. after Miller's attorneys requested the arrest of Lawrence Fred Grayson, an employee of a Riverside private investigator. Miller's lawyers claim that Grayson can substantiate the former FBI agent's claims that he was involved with Soviet immigrants Svetlana Ogorodnikova and Nikolai Ogorodnikov in a legitimate FBI capacity and not as a spy. Assistant U.S. Atty. Russell Hayman told the judge that there is no need to arrest Grayson because the government is in frequent contact with him and may call him as a government witness in the case. The espionage trial of the Ogorodnikovs is scheduled to start Tuesday, with Miller's trial to follow.