PORTLAND, Ore. (KOIN) – A man was arrested Thursday for allegedly helping his girlfriend die by suicide in The Dalles in March – using an idea from an infamous Massachusetts case that made national headlines.

Joseph Newman, 60, will face charges for manslaughter in the second degree after investigators say he bought a gas powered water pump, fueled it up and showed Alexander Cagle, 29, how to start it. 

Cagle then took the U-Haul truck they had rented together to a parking lot, where she started the machine and died, according to the Wasco County District Attorney’s office.

District Attorney Matt Ellis said he was originally hesitant to take it to the grand jury, but eventually felt he “owed it to the victim’s family to at least put this in front of the grand jury and let them decide. Ellis said he looked for precedent cases, too, and “didn’t see much case law that came after the seventies on this particular theory of manslaughter in the second degree.”

Ellis said Cagle suffered from mental health issues and had previously spent some time in the Unity Hospital in Portland, where Newman picked her up. According to Ellis, Cagle sent Newman an article about the infamous Michelle Carter case in Massachusetts and said she wanted to do something similar.

Carter had been convicted for texting and encouraging her boyfriend, Conrad Roy, to use a generator in his truck to create carbon monoxide poisoning.

“It’s one of those areas where…this person’s behavior is quite disturbing and an abhorrent that – to be in this relationship with somebody who’s suicidal – to give them the means to do something like this,” Ellis said. “It’s a very gray area of our legal system.”

Stay with KOIN 6 as this story develops.