He was a pro euthanasia advocate and was being questioned for murder following the death of a woman who died using a suicide pod dies of Suicide.
Dr. Florian Willet suffered a mental health crisis after he was arrested by Swiss police in September last year, said Philip Nitschke, the inventor of the Sarco suicide capsule.
Willet was the director of Last Resort, the Swiss suicide organisation, which was set up to facilitate the use of the Sarco.
The 47-year-old German was under investigation having been accused of aiding and abetting suicide. Prosecutors also investigated whether he had strangled the woman, but that was ruled out before he was released in December after 70 days in detention.

Death Capsule
“Gone was his warm smile and self-confidence. In its place was a man who seemed deeply traumatised by the experience of incarceration and the wrongful accusation of strangulation,” said Mr Nitschke, the director of Exit International, the pro euthanasia group.
The Australian former physician, who is called “Doctor Death” by his critics, said Mr Willet sought help and was admitted to a psychiatric hospital twice before his death on May 5.
Suicide is legal under certain conditions in Switzerland, but the pod had never been used before and there were warnings it would be illegal.
Willet was the only person present when a 64-year-old American woman, who has not been named, pressed a button to fill the Sarco pod with nitrogen gas. The woman had suffered from an immune disease.
He informed the authorities after her death in a forest in the canton of Schaffhausen but was arrested, along with several others, including a newspaper photographer.
They were later released but Willet, a former media spokesman for euthanasia clinic Dignitas, continued to be detained. He had described the first death in the controversial Sarco pod as “peaceful, fast and dignified”.
The 3D-printable capsule cost about £550,000 to research and develop in the Netherlands over 12 years. Last Resort has said that future reusable pods could cost about £12,600.