Half has a lot of stuff on this guy
https://boards.4chan.org/pol/thread/275219088
Big take is Reinoehl was cited for an illegal firearm at an earlier rally but that the charges were dropped.
https://www.oregonlive.com/crime/2020/08/man-under-investigation-in-fatal-shooting-after-pro-trump-rally-allegedly-took-loaded-gun-to-earlier-portland-protest.html
Family member going to cops, according to pol, is his sister. She and the family were threatened, they say.
From the linked article:
"Reinoehl’s 36-year-old sister said she was awakened just before 8 a.m. Sunday by a threatening phone call from someone who told her that “our whole family was in danger unless we turned him over.”
“That’s how I found out,” that her brother was allegedly involved, she told The Oregonian/OregonLive.
She called Sandy police to report the threat, she said. Once she looked online and saw screenshots of her brother’s photo, she said she called Portland detectives.
“We reached out to police and confirmed that we recognized Michael in the screenshots,” she said. She asked that her name not be used because of the threats.
Michael Reinoehl has been estranged from the family – including her, their parents and a younger brother – for at least three years, his sister said.
“On the one hand, this whole thing surprises the daylights out of us, because we always thought he is a lot of bark, not a lot of bite,” she said. “But he’s also been very impulsive and irrational.”
Reinoehl has stolen their mother’s seizure medication and owes a lot of debt, often giving his relatives’ addresses as his own to avoid responsibility, she said."
Pol/PTG doesn't add anything to that, or hasn't so far.