Here is a little info that might not be well know and a reason why BLM LEO's are a different animal compared to LEO's such as Sheriffs or Police Officers. During a race a few years ago I was talking with the BLM Rec Planner who was in charge of the race and we watched as the assigned BLM LEO's got out of their trucks with flak jaks on, Glocks with belts of ammo and assumed the cop stance with hands on the hips at a race and I laughed. We were at a race with the best people in the world that would share anything you needed, not at some civil uprising.
So I ask the Rec Planner why does he not apply for the raise and get to wear a Flak Jak, carry a Glock and just drive around all day. He then told me that he does not even qualify to put in an application for the upgrade due to that BLM has a stipulation that you can not be a LEO unless you have been discharged from one of the four military branches.
Basically he told me that all LEO's have been to boot camp, broken down, rebuilt with the combat attitude, trained with all sorts of weapons with the willingness to use them. He also said isn't weird that you can apply for the Secret Service and protect the president, be a local Sheriff protecting our law abiding citizens, all with out a military background.
I never researched his statements or have the time to do so, but he is a honest guy and I would have no reason not to believe him.
I personally call BS. I work for a different agency in the dept, so no first hand knowledge of BLM but I know enough about federal hiring practices that I can all but guarantee that at least formally, no agency can mandate that you must have a military background to fill an LEO job. No agency would attempt to formalize it because under federal rules it would subject them to all sorts of vulnerabilities for unfair hiring practices.
What they COULD do is informally only be hiring prior military dudes because that's their preference, and they can do it under the guise of claiming that those guys are the "most qualified", which speaks more to the good ol boys practices many find appalling about the bureaucracy but again, to my knowledge it's not even legal for an agency to have that kind of qualification requirement.