An advocate for euthanasia who was involved in the controversial Sarco suicide pod has died by suicide himself — just months after he was arrested when an American woman became the first to die by the invention.

Dr. Florian Willet — who headed up a pro-euthanasia organization called The Last Resort, an affiliate of Exit International that offers free assisted suicide services — spent a few months locked up after being hit with aiding and abetting suicide charges over the woman’s death last September.

Dr. Philip Nitschke, head of Exit International, says even though the charges didn’t stick and Willet was cleared of intentional homicide in December, he emerged from jail a changed man.

Sky News reports the 47-year-old Willet fell from the third story of his Swiss apartment building in January — unclear if intentional or not — and after surgery and months of rehab, he died by assisted suicide in Germany, according to Nitschke. The means of his assisted suicide were not revealed.

ICYDK, Willet was present when a 64-year-old Midwestern American woman became the first to die using the Sarco pod last year … sparking huge controversy.

Assisted suicide’s been legal in Switzerland since the 1940s — but the Sarco pod hadn’t gotten the green light from Swiss officials when it was used for the first time last year.

The 3-D printed Sarco pod works by flooding a sealed chamber with nitrogen gas — putting the user to sleep before they quietly suffocate. There’s a button inside that the person has to press to release the gas … a key detail, since Swiss law requires the individual to initiate their own death. Prosecutors alleged the device malfunctioned and the woman died by strangulation.