In December 2011, Louis Dabdoub Jr., then the chief investigator for the 22nd Judicial District Attorney’s Office in St. Tammany and Washington parishes, swore out an arrest warrant for felony theft and damage to property, plunging restaurateur Ricky Cambre into a two-year legal nightmare.

But on Tuesday, Dabdoub was himself charged with a crime stemming from that same warrant. A St. Tammany Parish grand jury indicted him on a single count of false swearing for the purpose of violating public health or safety.

State Assistant Attorney General David Caldwell sought the charge, saying Dabdoub made a false statement to get Cambre arrested in an attempt to help a close personal friend and supporter of the District Attorney’s Office who was suing Cambre.

That friend was Barbara Marullo, who owned the Covington building that housed Cambre’s Ground Pat’i restaurant. Her husband, Anthony Marullo, had served on the New Orleans Police Department with Dabdoub as well as former District Attorney Walter Reed and Sam Gebbia, another investigator for the district attorney.

“It’s a very egregious abuse of power when you cause someone to be arrested and you lie in an affidavit,’’ Caldwell said, saying such actions cause people to lose confidence in the justice system.

Caldwell said he does not believe that Reed, who was DA at the time, knew anything about the case and that Reed’s office ultimately dropped the charges and paid a settlement of about $40,000 to the falsely accused man.

But he said the Cambre case is “just one aspect of an ongoing investigation into the abuses of power by certain individuals in the former (Reed) administration.’’

The Attorney General’s Office is working with the FBI and the state Inspector General’s Office on other cases that have been brought to light mainly by the Metropolitan Crime Commission. Caldwell said he could not comment on the facts or targets of those investigations but that the files will be complete in mid- to late December and will be presented to a grand jury shortly thereafter.

Dabdoub left the District Attorney’s Office before Warren Montgomery was sworn into office early this year, succeeding Reed. But while Dabdoub was still chief investigator, he claimed in a sworn affidavit that Cambre had told Barbara Marullo he took parts from a restaurant cooler and filled in a drain with cement.

In a sworn deposition in her civil suit, however, Marullo denied ever telling anyone that Cambre had admitted to anything. In an interview with Dabdoub and Gebbia, she said she had never even spoken to Cambre.

The problems in the criminal case were spelled out in a memo obtained by The New Orleans Advocate. Jack Hoffstadt, the assistant district attorney who was assigned the case, said in the memo, dated July 24, 2013, that the Sheriff’s Office had found insufficient evidence to charge Cambre and that the alleged victim herself contradicted the account in the affidavit for Cambre’s arrest. He also said the investigators never provided him with a written report and tape that they said would back up their story.

“I do not believe this is a case that should be tried,’’ he concluded. The District Attorney’s Office dropped the case that same day.

Hoffstadt, who has since left the office, testified before the grand jury Tuesday.

Gordon Herrin, who represented Cambre in the criminal case, described his client as a “Boy Scout,” an upstanding businessman who plays by the rules.

“He’s the last person you’d accuse of taking copper tubing to sell for scrap,’’ Herrin said.

Cambre was arrested in Lafayette, where he now lives, in February 2012 and was taken to St. Tammany Parish, where he was locked up, Herrin said. He had to make frequent trips to St. Tammany after that and faced two years of legal bills.

Cambre’s dispute with the Marullos was over rental payments and was not a criminal matter, Herrin said, and he brought the arrest and the false information on which it was based to the attention of the Marullos’ civil attorney, who wrote a letter to the District Attorney’s Office in April 2012. But the case wasn’t dropped until July 24 of that year.

Herrin said he had a face-to-face conversation with Dabdoub in late spring 2012 in which the investigator said the charges would be dropped “if Mr. Cambre signed a waiver of liability against the DA’s Office.’’

Herrin said he replied that he would see Dabdoub in court.

He called the case shocking, saying every District Attorney’s Office he’s dealt with has played by the rules. “This was clearly a case where the arrest should never have taken place,’’ he said.

Dabdoub’s attorney could not be reached for comment.

Follow Sara Pagones on Twitter, @spagonesadvocat.