Boeing Whistleblower John Barnett Died by Suicide, Coroner Says

The Charleston Police Department said in a May 17 statement that Barnett died of an apparent self-inflicted gunshot wound to his head

• Boeing whistleblower John Barnett's cause of death has been determined.

• Before his death, the whistleblower, who spent about 30 years with Boeing, raised various alleged safety concerns about the planes.

• "Barnett’s longstanding mental health challenges had intensified in connection with ongoing legal proceedings related to his whistleblower case," the Charleston Police Department said.

The cause of death of former Boeing quality control manager John Barnett has been determined.

The 62-year-old Louisiana man died by suicide on March 9, the Charleston County Coroner's Office said, according to a statement from the Charleston Police Department, obtained by PEOPLE on Friday, May 17.

At the time of his death, the Charleston County Coroner's Office said in a statement obtained by PEOPLE that Barnett died of an apparent self-inflicted gunshot wound to his head. He was found dead in his car in the parking lot of his Holiday Inn hotel, located at 301 Savannah Highway.

The Charleston Police Department said in the May 17 statement that there was “no evidence of forced entry was found and there were no signs of a physical struggle within the vehicle."

"Information and records reviewed during the investigation uncovered Mr. Barnett’s longstanding mental health challenges, which had intensified in connection with ongoing legal proceedings related to his whistleblower case," police said.

Related: Boeing-Linked Whistleblower Dead, the Second in 2 Months: ‘He Possessed Tremendous Courage,’ Lawyers Say

Additionally, the Charleston Police Department said a notebook was found on the front passenger seat of the vehicle, which “included a note from Mr. Barnett that suggested he was going through a period of serious personal distress.”

In a statement in March, Barnett's family said he experienced post-traumatic stress disorder and anxiety, claiming that the “hostile work environment at Boeing” led to his death, reported NBC News.

“John told us that every day was a battle to get management to do the right thing,” the family statement read. “He was looking forward to having his day in court and hoped that it would force Boeing to change its culture.”

Barnett, who worked at Boeing for about 30 years before his 2017 retirement, was in Charleston, S.C., to testify in his whistleblower case against Boeing after he alleged safety concerns, reports Time and the BBC.

The United States Department of Labor was working through the discovery phase of its investigation and is set to begin hearings on that complaint this June.

"John was in the midst of a deposition in his whistleblower retaliation case, which finally was nearing the end," his lawyers, Robert Turkewitz and Brian Knowles, said in a statement obtained by PEOPLE in March.

Related: Boeing Whistleblower Reportedly Claims 787 Planes Could Break Apart Mid-Air Due to Construction Flaws

"He was in very good spirits and really looking forward to putting this phase of his life behind him and moving on. We didn’t see any indication he would take his own life. No one can believe it," they added. "We need more information about what happened to John. The Charleston police need to investigate this fully and accurately and tell the public what they find out. No detail can be left unturned."

The BBC reported that he gave a formal deposition and was questioned by Boeing's lawyers the week before his death and was scheduled to undergo additional questioning that Saturday.

Barnett first filed a complaint with the Occupational Safety and Health Administration in January 2017. He accused Boeing of retaliating against him, but the agency determined there was none. He appealed the decision, according to The Washington Post.

Two years later, in an interview with the BBC, he claimed employees were under pressure to intentionally fit aircraft with substandard parts on the production line. He also told the outlet about his concerns with the oxygen systems on Boeing’s 787 Dreamliners. He alleged that one in four breathing masks would not work in the event of an emergency.

Barnett’s death follows the recent public scrutiny of Boeing after a number of public incidents — including when a part of a Boeing aircraft blew out mid-flight on an Alaska Airlines trip and when 50 people were injured on a Boeing 787-9 Dreamliner when a sudden mid-air movement caused the plane to drop suddenly.

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If you or someone you know is considering suicide, please contact the 988 Suicide and Crisis Lifeline by dialing 988, text "STRENGTH" to the Crisis Text Line at 741741 or go to 988lifeline.org.

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