Louisiana’s legal watchdog agency is investigating the controversial use of so-called “fake subpoenas” to pressure witnesses to speak with prosecutors, its chief said Thursday.

The Office of Disciplinary Counsel is conducting a statewide inquiry into the documents issued by district attorneys, Charles Plattsmier said.

Prosecutors in Orleans and Jefferson parishes have acknowledged sending notices stamped “subpoena” to witnesses without receiving court authorization.

“From the outset we were aware of and we have begun looking into the practice of the issuing of the subpoenas, or documents that do not comply with the Code of Criminal Procedure in criminal cases, so-called ‘district attorney subpoenas,’ ” said Plattsmier, the agency’s chief disciplinary counsel.

Plattsmier said the probe began around the same time that the longstanding practice was revealed by the Lens, a nonprofit news outlet in New Orleans.

The Office of Disciplinary Counsel has the power to recommend legal sanctions against lawyers who violate ethics rules in Louisiana. If contested, its decisions must be ratified by the Louisiana Attorney Disciplinary Board and state Supreme Court before taking effect.

Attorneys can receive a public reprimand or the suspension of their license if they are found to have engaged in misconduct.

The confirmation of the agency’s probe came on the same day that a civil rights group said it was filing ethics complaints against Orleans Parish District Attorney Leon Cannizzaro and Jefferson Parish District Attorney Paul Connick Jr. because of the practice.

Both offices used the “fake subpoenas” for years or even decades, but they announced they were ending the practice after it was made public. Cannizzaro told WWL-TV in April that he regretted the practice.

"It was improper for us, it was incorrect for us, to label those notices as a subpoena," he said. "That was incorrect. It was improper, and I take responsibility for that."

The Southern Poverty Law Center said in its ethics complaints lodged with the Office of Disciplinary Counsel that it wants the agency to conduct an investigation to see which prosecutors actually sent the “fake subpoenas.”

Cannizzaro’s office is fighting public records lawsuits that seek to force disclosure of the names of individual assistant district attorneys involved in the practice.

The SPLC said in its filing that a full-scale investigation is needed to prevent future abuses from occurring. It said the subpoenas in Orleans — which raised the prospect of jail time for witnesses who did not comply — may have constituted fraud.

“Investigating and sanctioning the unethical conduct will deter prosecutors across the state from engaging in similar misconduct and protect the integrity of the legal profession,” the group said.

The Office of Disciplinary Counsel has not confirmed whether it is investigating individual prosecutors at the district attorneys' offices. However, the agency does have the power to subpoena prosecutors for more information.

A spokesman for Cannizzaro’s office said it has not received formal notice of the Southern Poverty Law Center complaint.

“When and if we are asked to respond to it, the District Attorney’s Office will do so according to the rules of professional conduct,” Christopher Bowman said.

Connick's office had no comment.

Follow Matt Sledge on Twitter, @mgsledge.

msledge@theadvocate.com | (504) 636-7432