23 and me does not "publish" your DNA and your personal details. If you opt in to share, you can share just there is a percent match, with no details, or greater number of details, like family names and geographic locations, with out drilling down to exact detail, or you can choose to bare it all.
So if Law Enforcement uploads a sample and gets a hit, it means you have opted in to the point your DNA can be matched. they would need to contact the customer through the sw to ask for more info, if that was not shared. That person can ignore or comply with that request.
I get a lot of third cousins. That is people related to my great grandparents. I would think a judge might be disinterested in forcing a third cousin to reveal themselves, as literally, thousand of people can be related in that way, and that scope is pretty large.
Obviously, there have been cases where DNA has been forced from residents in large areas to try and track a criminal, but that would need to be an extra ordinary circumstance. If the match was immediate family, like brother sister mother father,. I think a judge would try and compel 23 and Me to disclose the results if it were a serial killer. That might go to the courts.
It seems the results you see in the news if where a person has disclosed who they are and their antecedents, and genealogy is used to trace down to a likely suspect, based on location and time, and then follow them around to pick up a used cup or cigarette butt to prove the match.
It's not a slam dunk, if the FBI has a .78% match (that is POINT 78 percent) and in a small regional area, maybe that half the population for the last 100 years is related at that level.
The board walking out has to do with money and power, not privacy issues of customers.
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