Billy Carter lied when he told federal investigators in January that he had not received any money from Libya, according to Justice Department files.

The records show that the Libyans wrote a $20,000 check to the president's brother on Dec. 27, nearly three weeks before he was interviewed by investigators Jan. 16.

Joel Lisker, head of the department's foreign agents registration unit, told the Associated Press yesterday that he received a deposit slip on the transaction Tuesday that showed Billy Carter deposited the check in his bank account Dec. 31.

"There's no doubt he knew at the time [of the Jan. 16 interview] that he had received the money," Lisker said.

On the sworn registration statement he filed with the Justice Department two weeks ago, Billy Carter said he received the $20,000 payment in January.

A willfully false statement in the regristration statement is punishable by five years in prison and a $10,000 fine. But Lisker said he was not going to pursue the misstatement.

"I'm not going to go off on something like that," Lisker said. "He didn't have the deposit slip when he made the registration statement."

Department officials have said that Billy Carter would not be prosecuted even if he did lie to them in unsworn interviews because department policy is that false oral statements under such circumstances are punishable only if volunteered, rather than in answer to a question. (See BILLY, A12, Col. 5>

Rep. Harold Sawyer (R-Mich.) said yesterday that his review of the files the department made available to the House showed that Billy Carter also lied to investigatiors in June by calling the $20,000 a reimbursement of his expenses from escorting a Libyan delegation around the United States.

In his registration statement, Carter described the $20,000 as a loan rather than a reimbursement of expenses.

Sawyer said that in his first interview Carter told Lisker and the FBI that he had received "only a few gold bracelets" and reimbursement of $6,000 to $7,000 in expenses from the Libyans' trip in this country.

When asked about his gifts from Libya in a June 11 interview with Justice officials who knew of the $20,000 payment, Carter claimed he had run up expenses of $40,000 -- and the $20,000 was partial reimbursement -- according to Sawyer.

"Billy Carter has been far from forthcoming, " Rep. Thomas F. Railsback (R-ill.) said yesterday after reviewing some of the Justice Department documents in the case, including interviews with the president's brother. "Billy Carter's been all over the lot. He's given inconsistent answers."