An attorney for Paul Carpenter, who is under indictment from the FBI undercover investigation of alleged political corruption in the state Capitol, says the former state senator suspects that his telephone was illegally tapped and that someone broke into his home in Los Angeles County during the investigation. Attorney Jerrard Hinckley reported Carpenter's suspicions to U.S. Magistrate Esther Mix during a federal court hearing on routine pretrial motions. Prosecutors said they had no knowledge of any such illegalities, but promised to investigate. Hinckley said Carpenter found his home unlocked and lights on once about a year ago, and later saw a man working on a telephone pole near his home. "He was told a neighbor had a phone problem, but he checked . . . and none had complained of phone problems," Hinckley said. Carpenter, now a member of the State Board of Equalization, is to go on trial Aug. 13 on felony charges of extortion, racketeering and conspiracy.