Federal authorities apparently are continuing to investigate a once-rejected case involving alleged sexual misconduct by former longtime St. Charles Parish District Attorney Harry Morel. At least one new subpoena was issued in the past month.

Although the U.S. Attorney’s Office in 2013 declined to bring charges against Morel, The New Orleans Advocate reported last year that the case was getting a fresh look from the office.

The allegations in the case focus on claims that Morel sought sexual favors from women in exchange for giving them breaks on criminal cases. Through his lawyer, Ralph Capitelli, Morel has denied the allegations.

St. Charles District Attorney Joel Chaisson II, who followed Morel in office, this month received a subpoena from a federal grand jury, according to a two-page letter released in response to a public records request from The Advocate.

Chaisson declined to provide a copy of the subpoena, citing provisions of the public records law that exempt documents tied to pending criminal litigation. “The documents you requested fall within the above exception based upon representations from federal authorities,” he wrote.

Reached by phone, Chaisson declined further comment.

It’s unclear what records federal investigators were after or who else may have received recent subpoenas in connection with the case. FBI spokesman Craig Betbeze declined comment Friday.

Morel has been out of office since June 2012. After resigning, he continued working as an assistant district attorney under Chaisson until early 2013.

As part of its probe, the FBI last summer subpoenaed a decade’s worth of records of child support cases from St. Charles Parish Clerk of Court Lance Marino. The cases involved “child support enforcement actions taken by the District Attorney’s Office” from June 1, 2002, to May 31, 2012.

The records were to be produced for a federal grand jury meeting in New Orleans, according to U.S. Attorney Kenneth Polite’s office.

At the time, the clerk’s subpoena was the third that the FBI had served to Marino in connection with the case.

The case against Morel appeared to suffer a major blow in 2013 when a woman who was expected to be a key witness for the government, Danelle Keim, 27, died of a drug overdose.

The New Orleans Advocate has reported that evidence in a related case suggests Keim was wearing a wire at the FBI’s request in the months before her death.

Among the 457 cases listed in the 2014 subpoena was a November 2012 custody case between Keim and her ex-husband, Darren McGovern, who ultimately was awarded primary custody of their young son.

The feds also were exploring allegations that Morel had improperly traded leniency in exchange for sexual favors from a second woman, Melissa Silvestri. She also died of a drug overdose, in February 2014.

Capitelli, Morel’s lawyer, declined to comment Friday.

Previously, Capitelli has criticized federal investigators for continuing to dig into a case that already was refused once by prosecutors.

“I can tell you right now, there’s not a specific allegation I know of that involves a single impropriety on the part of Harry Morel,” Capitelli said at the time.

Follow Richard Thompson on Twitter, @rthompsonMSY.