Already foaming with vitriol, the case of a New Orleans public defense investigator accused of impersonating a District Attorney’s Office staffer turned testier this week, with a retort from Orleans Parish District Attorney Leon Cannizzaro’s office to allegations of a malicious prosecution.

Claims that Cannizzaro’s office concocted an indictment against 24-year-old investigator Taryn Blume as payback for allegations of ethical misconduct were met with scorn and a thinly veiled threat against her attorneys.

Cannizzaro’s office also accused those lawyers of inventing a controversy between the district attorney and Chief Public Defender Derwyn Bunton’s office to justify their bid to have Cannizzaro and his office, along with prosecutor Jason Napoli, tossed from the case.

The District Attorney’s Office describes as “laughable” the allegation that Napoli concealed evidence in a case that ended in December with http://theadvocate.com/features/carnival/10993102-123/new-orleans-man-found-guilty">a jury convicting Curtis Hawthorne, 23, of aggravated rape, aggravated kidnapping and armed robbery in a Mardi Gras 2013 assault on a University of Texas senior.

Still more of a joke, according to the district attorney, is the idea that Blume is being prosecuted out of malice.

She is accused of posing as an investigator for Cannizzaro’s office when she approached New Orleans Housing Authority police last year about Hawthorne’s case. Blume has pleaded not guilty.

Her attorneys, Mark Cunningham and former federal prosecutor Michael Magner, of the Jones Walker firm, say the indictment amounts to “an unprecedented effort” to obscure a prosecutor’s failure to disclose evidence and “to retaliate against public defenders who bring prosecutorial misconduct to the attention of the courts.”

In a sharply worded, 18-page legal filing Wednesday, Assistant District Attorneys Christopher Bowman and Kyle Daly and First Assistant District Attorney Graymond Martin threatened to lodge a formal complaint against Blume’s attorneys if they can’t prove their “torrid allegations.”

Cannizzaro’s office also has asked Criminal District Court Judge Tracey Flemings-Davillier to hold Magner and Cunningham in contempt. Cannizzaro’s office scoffed at the idea that defense lawyers could joust with the District Attorney’s Office, then cite that conflict in trying to recuse prosecutors.

“If an individual can immune him or herself of criminal prosecution simply by cursing the very organ of government that enforces the law, then this whole community will soon find itself on a speed boat to the island of anarchy,” Bowman wrote.

At issue in the allegation of misconduct is a HANO log that defense attorneys claim Napoli withheld in Hawthorne’s case. They formally lodged that allegation in a motion for a new trial that Criminal District Court Judge Franz Zibilich rejected.

That challenge followed Blume’s indictment on a charge of impersonating a peace officer. Cannizzaro’s office claims the timing proves Napoli wasn’t retaliating when he brought the allegations against Blume before a grand jury.

Blume’s attorneys contend the legal jousting over the evidence started earlier and that Blume’s indictment was a diversionary tactic.

Napoli claims he never saw the HANO log, blaming Blume for misleading HANO police.

It was only after Blume’s attorneys failed to convince Cannizzaro to drop the charge against her that they “unleashed their torrid allegations of prosecutorial misconduct,” the DA’s Office claims.

Loyola law professor Dane Ciolino, a frequent legal commentator, argued in an affidavit on Blume’s behalf that Napoli and Cannizzaro have a “personal interest in the outcome of these proceedings” and should be barred from her prosecution.

Magner declined to comment on Cannizzaro’s latest legal filing.

“However, we do wish to categorically state that the evidence at trial will demonstrate without any doubt that Ms. Blume never held herself out as an investigator for the district attorney and that we advised the district attorney of that fact during our meeting with him and Mr. Napoli in the clearest possible terms,” Magner said.

Cannizzaro has mischaracterized those talks, Magner added, lending “further evidence that neither he nor his office can be relied upon to handle this matter with the requisite professional judgment.”

The case is set to return to court next week.

Follow John Simerman on Twitter, @johnsimerman.