A former commander of the US Navy base at Guantanamo Bay was convicted Friday of interfering with an investigation into the death of a civilian with whom the commander had fought and argued over his affair with the man’s wife.

A federal jury in Jacksonville convicted Navy Captain John R Nettleton on charges of obstruction of justice, concealing material facts, falsifying records and making false statements.

Nettleton was removed from command shortly after civilian Christopher Tur was found floating in the waters off the base on the southeastern coast of Cuba in January 2015. Nettleton had commanded the base since June 2012, but not the detention centre where suspected terrorists are held.

Nettleton wasn’t charged with Tur’s death. He could get 75 years, but sentencing guidelines suggest his term will be significantly less.

Guantanamo Bay detainee illustrates torture he faced at US black site Show all 8 1 /8 Guantanamo Bay detainee illustrates torture he faced at US black site Guantanamo Bay detainee illustrates torture he faced at US black site A Guantanamo Bay detainee illustrates the torture he faced in US custody. The graphic illustrations show the various forms of torture Abu Zubaydah said he experienced at a US black site in Thailand. Abu Zubaydah, Courtesy Professor Mark P. Denbeaux, Seton Hall University School of Law Guantanamo Bay detainee illustrates torture he faced at US black site The detainee was tied up in painful positions. Mr Zubaydah illustrated multiple examples of the ways he was forced to suffer while chained and tied in painful positions. Abu Zubaydah, Courtesy Professor Mark P. Denbeaux, Seton Hall University School of Law Guantanamo Bay detainee illustrates torture he faced at US black site He was confined to a small box. Unable to stand or sit up straight, Mr Zubaydah described being forced to crawl into a box for endless hours while in the fetal position. Abu Zubaydah, Courtesy Professor Mark P. Denbeaux, Seton Hall University School of Law Guantanamo Bay detainee illustrates torture he faced at US black site Mr Zubaydah suffered through "walling" according to his illustrations The "walling" process involves slamming a detainee's head against the wall. Mr Zubaydah said he was slapped and dragged across the floor by a towel. Abu Zubaydah, Courtesy Professor Mark P. Denbeaux, Seton Hall University School of Law Guantanamo Bay detainee illustrates torture he faced at US black site Officials waterboarded the detainee 83 times. Mr Zubaydah told his lawyers: "They kept pouring water and concentrating on my nose and my mouth until I really felt I was drowning and my chest was just about to explode from the lack of oxygen.” Abu Zubaydah, Courtesy Professor Mark P. Denbeaux, Seton Hall University School of Law Guantanamo Bay detainee illustrates torture he faced at US black site Mr Zubaydah shows how he was forced to stand. With his hands tied high above his head, the detainee was forced to endure long hours while standing on his tiptoes. Abu Zubaydah, Courtesy Professor Mark P. Denbeaux, Seton Hall University School of Law Guantanamo Bay detainee illustrates torture he faced at US black site He also faced significant sleep deprivation. Officials doused the detainee with water and forced him to stay awake for prolonged hours, according to his statements and illustrations. Abu Zubaydah, Courtesy Professor Mark P. Denbeaux, Seton Hall University School of Law Guantanamo Bay detainee illustrates torture he faced at US black site The detainee was not provided proper hygiene. On top of the "enhanced interrogation" techniques Mr Zubaydah endured, he was also forced to defecate in a bin underneath him in a small box, or at other times as he was strapped to a chair. Abu Zubaydah, Courtesy Professor Mark P. Denbeaux, Seton Hall University School of Law

“Nettleton dishonoured his oath and impeded the investigation into a civilian’s tragic death, preventing much needed closure for the family and friends of the deceased,” Assistant Attorney General Brian Benczkowski said after the verdict, according to The Florida Times-Union. “Today’s verdict demonstrates the department’s steadfast commitment to holding accountable those who abuse their positions of public trust and obstruct justice.”

Tur’s siblings issued a statement thanking prosecutors and the jury, but added “unfortunately this trial has brought us more questions. ... We will not stop until we have answers.”

Nettleton denied to his superior officer and others that he had the affair, but investigators later determined that it had happened, according to prosecutors in Jacksonville, where Nettleton had been on temporary duty. Tur’s wife confirmed the affair during her testimony.

Defense attorneys argued that Nettleton couldn’t be found guilty of any of the charges merely for violating provisions of the Uniform Code of Military Justice or for violating any Navy regulations.

An autopsy found that Tur, 42, died from drowning but that his ribs had been fractured before he went into the water and he had a cut to his head. The investigation also turned up Tur’s blood inside the entryway of Nettleton’s residence on the base and on a paper towel in the backyard.

Tur came to Guantanamo in May 2011 with his wife, Lara, and two children and worked as the loss prevention safety manager at the Navy Exchange, the main shopping complex on the base.

On the night of his disappearance, Tur confronted the commander and Tur’s wife in front of witnesses at a party at the on-base nightclub. Each had “consumed several alcoholic drinks,” according to the indictment.

Later that night, Tur went to Nettleton’s residence, where the two men fought. Nettleton’s daughter heard the commotion and came down to see her father on the ground and Tur standing over him shortly before he left the area and wasn’t seen again.

Around that time, a friend of Tur’s reported getting a call from Tur, who said he was at Nettleton’s house and had “just knocked the skipper out.”

After Tur went missing, Nettleton failed to tell people leading the search for him that he was last seen at Nettleton’s house when they fought, and the commander instead led them to believe he was last seen at the nightclub, according to prosecutors.