The Treasury Department's top ethics cop is investigating circumstances surrounding a decision by a federal bank examiner to join Riggs Bank as a vice president, just weeks after he left the government in 2002.

The Treasury Department's acting inspector general, Dennis S. Schindel, disclosed the probe yesterday during a congressional hearing on money laundering. He said he has told the Office of the Comptroller of the Currency (OCC), a unit of the Treasury Department where the examiner worked, that it would be a conflict of interest for OCC to investigate the matter.

The examiner, R. Ashley Lee, was "examiner in charge" of Riggs from 1998 to 2002, the years regulators and federal law enforcement officials at Treasury say the bank repeatedly violated anti-money-laundering rules.

Last month the OCC and the enforcement unit of Treasury fined Riggs a record $25 million for failing to report suspicious transactions -- particularly those connected to embassy accounts for Saudi Arabia and Equatorial Guinea. The OCC, the FBI and several congressional committees continue to probe Riggs. Several members of Congress, including Sue W. Kelly (R-N.Y.), who chaired the House Financial Services subcommittee hearing, have criticized the OCC for failing to unearth violations of anti-money-laundering laws years sooner in several widely publicized cases, including Riggs.

Kelly and Senate Banking Committee Chairman Richard C. Shelby (R-Ala.) have questioned whether bank regulators' failures indicate responsibility for policing for money-laundering should be given to other agencies.

In response, Comptroller of the Currency John D. Hawke Jr. in recent weeks launched a probe of his agency to determine why the years-long abuses at Riggs went uncorrected for so long.

Hawke said he would probe issues including Lee's conduct to determine whether the bank exerted "inappropriate influence" on regulators. He also said he would determine when the bank offered Lee employment.

Schindel said that when he read about Hawke's probe into Lee, he immediately called the OCC's chief counsel, Julie L. Williams, and said such an inquiry was a conflict because it amounted to the OCC investigating itself. He said he told Williams the inspector general's office would take over the probe.

Officials from the OCC could not be reached yesterday afternoon. Riggs has said Lee will not comment.