Isn’t that a pretty significant category of ‘minor celebrity,’ though - someone who’s well-known in a certain field or to fans of a particular entertainment niche, but not famous with the general population?
Anton Yelchin wasn’t well-known? 
How about Marion Zimmer Bradley. She was known as a science fiction/fantasy writer. But then she was a central figure in a child abuse scandal.
Bernie Madoff and Harvey Weinstein come to mind. Madoff was known in finance world and more than a few celebs lost money in his scam, Kevin Bacon as an example.
This is all very dark. Here’s something British and not so dark: Gillian Taylforth managed to fulfill the requirements of the OP via a spectacular example of the Streisand effect:
She was a pretty successful soap actress; and became the subject of a salacious story in a tabloid newspaper. So:
It would be a stretch to call it lighthearted but, hey, nobody died.
j
I wouldn’t have heard of Yoshiyuku Takada if he hadn’t fallen to his death in a freak accident during a performance in 1985. His butoh dance troupe Sankai Juku was suspended upside down from the Mutual Life Building in Seattle when his rope broke. I probably wouldn’t have heard of Sankai Juku at all if not for Takada’s death. In fact, the news of his death was the first time I learned of the existence of butoh at all.
Peg Entwistle was basically a nobody who became incredibly well known for one thing: jumping to her death off the Hollywood sign.
If you come across any list on infamous Hollywood deaths, she is sure to be on it and will be the most obscure.
About 100 people gathered in 2014 to watch her only film Thirteen Women as a fundraiser for a suicide prevention group.
In her industry, she was anything but obscure. Her husband, Walter Breen, qualifies for this more, to my thinking. About the only reason he’s known outside of numismatic circles is because of his conviction for child molestation and his marriage to Bradley (and his personal pedophilia history was brought back into the public eye when Bradley had her own scandal that you mentioned).
It depends on how big that niche is. If the niche is Hip Hop I would argue that is pervasive enough to just be considered to be general pop culture. Just because I’m too old and its passed me by doesn’t change that fact.
Now that is a niche. Before or after that came out I doubt you would find anyone who knows that name who isn’t locked into reading science fiction and fantasy. And seeing the shrinking sci-fi section in Barnes and Noble I’m thinking that niche is getting smaller. I don’t know how widespread the crimes were reported. I am a science fiction fan and I learned about it here. I don’t remember it being heavily reported in the press.
Mostly people I never heard of before they died or got arrested.
Murder victims: Gianni Versace, Tupac Shakur, and Selena. Sal Mineo’s death happened before I started paying attention to the news or saw any of his movies. Though I’ve since seen at least two of his movies, I probably wouldn’t recognize his name if not for his murder.
Murderers: Aaron Hernandez, Sid Vicious, Oscar Pistorius, Christian Brando
Accident victims: Paul Walker, Natasha Richardson, and Payne Stewart. Also River Phoenix (I had seen two of his movies but when he died I didn’t recognize his name)
Other than Conrad Bain I think the entire cast of Different Strokes became more famous for various scandals.
Or Charlotte Rae or Danny Cooksey or Maryann Mobley.
David Paymer was on two episodes why didn’t you list him? Or Kareem Abdul-Jabbar? Or Nancy Reagan? The show was on for 181 episodes. There were a lot of people who had roles. You even left out the actor who was on the 5th most episodes Mary Jo Catlett. In context I think it was obvious I was talking about the main cast of the father and the children.
While it was for a “bad reason,” her notoriety due to the fact that she had made porn films while underage almost certainly benefited her career as a legitimate actress. I think she’s still just a “minor celebrity,” but if not for that she would be virtually unknown outside the porn world.
For this reason, a lot of people suspect that Lords secretly reported herself.
Yeah. For example, I’m pretty sure that I never heard of Amy [del]Crackhouse[/del] Winehouse before she died, but that’s just me.
Marion wrote at least one NY Times best seller, so she was a well-known author. She even ran a magazine with her name on it.
Breen, OTOH, was very obscure, and his scandal is pretty much the only thing people know him for.
Then you must have not been a Dead Pooler. She was a popular pick for years before she died.
How about Pee Wee Herman? Or is he beyond ‘minor’?
I can tell you a doozie of a story about this! 