The fallout from a blistering U.S. Department of Justice report spilled into the Evangeline Parish courts this week, as the public defender in Ville Platte asked a judge to throw out a 2014 murder conviction he claims was tainted by the unconstitutional arrest of a witness who was jailed and interrogated for hours following a fatal shooting.

The arrest of Shawana Deville, who was not accused of any crime, was among the most startling examples brought to light by the Justice Department investigation, which revealed that authorities in Evangeline Parish for decades detained witnesses, persons of interests and even their family members without the probable cause required to take them into custody.

The practice, known as investigative holds, became so common that local officials referred to it as putting people "on ice," and grew to rely on the indefinite detentions to bolster criminal cases that otherwise lacked evidence. It has since been discontinued by the Ville Platte Police Department and Evangeline Parish Sheriff's Office, which are working with the Justice Department to implement new policies and training. 

The federal government identified hundreds of illegal arrests over a period of three years, raising concerns about "coerced confessions and improper criminal convictions" that may permeate the 13th Judicial District Court. 

The public defender, Alex D. Chapman Jr., filed a motion for new trial this week in the case of Samuel Brent Anderson, a man convicted last year of armed robbery and first-degree murder in the killing of Ann Nguyen, a 59-year-old woman found fatally shot in her grocery store. Deville's arrest and subsequent questioning represented "a gross violation of constitutional rights," Chapman alleged, and a "prejudicial error" that poisoned Anderson's proceedings. 

While Deville said she did not testify in Anderson's trial, the Ville Platte police included her statements in their investigative reports, including her vague account of "a guy with a red mask and white shirt standing in the door of the store" who appeared to be "trying to get out." It's not clear from the report whether these statements affected the outcome of the investigation. 

Chapman filed the motion for new trial after Deville was identified in a news report by KATC-TV. She had not been named in the Justice Department report, which nonetheless revealed that the woman had been strip-searched and forced to remove her tampon before entering the jail's general population. 

The police insisted Deville had witnessed the robbery and shooting while grocery shopping, and an officer went to her home and took her — along with her boyfriend and a 16-year-old — into custody. "None of these individuals were suspected of having any connection to the robbery or shooting," the Justice Department report said, "yet detectives incarcerated them for significant periods of time before showing them a line-up and asking them questions about what they may have witnessed."

In a telephone interview Friday, Deville said the first person to interrogate her — after she changed into an orange jumpsuit —was Trent Brignac, the Evangeline Parish district attorney. She said Brignac told her she was "under investigation" and asked her "the same questions over and over again" until he was satisfied she had not witnessed the killing. 

Brignac has not returned calls seeking comment.

Ville Platte Police Chief Neal Lartigue confirmed Deville's account to the Justice Department, according to the government's report. But he told The Advocate last month he had no knowledge of the woman or her claims. "They didn’t release any names to us or confront us with any of that," Lartigue said about the federal investigators.  

Deville said she was held in the jail for about eight hours, a period she described as terrifying. She said she was too scared to ask her any of her fellow inmates why they were behind bars. 

The 16-year-old, Liljohn O'Neail, who is now 18, said he was held in the jail for about the same length of time and never even questioned. "It wasn't nothing fun once you get behind them gates, especially when you didn’t do nothing," he said. "I was shaking, kind of nervous a little. I didn’t know what was going on."

Follow Jim Mustian on Twitter, @JimMustian.