May 29, 2015 10:52 AM

PI Robert Williamson, aka "Secret Cajun Man"

The Advocate reports Friday that a federal judge has ruled comments private investigator Robert Williamson gave to federal agents when they searched his home in February 2012 can be used in Williamson’s trial, which ­ — after several delays — is set to start June 8.

Williamson, the PI who dubbed himself "Secret Cajun Man," is the accused linchpin in a pay-for-plea scheme centered on former District Attorney Mike Harson’s office, primarily involving DWI cases.

Williamson is charged with fraud, bribery and lying to a federal agent in a case that has already resulted in three guilty pleas from employees in the DA’s office, among them Harson’s longtime administrator, Barna Haynes, and two others who worked for a local nonprofit.

Although Harson was never charged, the scandal is widely credited for his re-election defeat last year.

The Louisiana Attorney General’s Office confirmed in November that it, too, is investigating the matter but has released no information on the scope of its inquiry. At that time, the office told The Independent that it was asked by the feds to determine whether any state laws were violated.

The Advocate speculates that defendants who allegedly gave Williamson money used for the bribes could be potential targets, as well as any other officials involved in the scheme but not targeted by federal authorities.

Assistant Attorney General David Caldwell, who heads the agency’s public corruption division, told The Advocate Thursday that the case remains active.

“We expect some movement in the near future,” he said.

Read the full Advo story here.