What documentation can I find on the subject of "Legal and the NCO Leader" out side of the manual for court martial?

SGT (Join to see), are you looking from a historical view or actual roles and responsibilities of a NCO during legal proceedings?

I.e., ... something like this - In 1849, a young man named Percival Lowe enlisted into the U.S. Army's elite Dragoon unit. Lowe use his knowledge of the land and equestrian skills to immediately make an impact in his unit. Lowe would achieve the rank of first sergeant in just over two years.

In 1853, Lowe, along with other NCOs in his company, established the "company court martial." It was not yet recognized by the Army, but this was the first time that NCOs could enforce discipline in their Soldiers for breaking regulations without dealing with lengthy proceedings.

or something like this, "NCOs have the authority to apprehend persons subject to the UCMJ pursuant UCMJ, Art. 7; RCM 302(b); and chapter 4 of AR 600-20."?

If the former, Google is your friend. Lots of different historical documents that you can sift though that will give you quite a bit of info.

If the latter, start with AR 600-20.

Reach out to the legal office for interpretations of the breadth of NCO authority. Pull up the AR’s and legal policy. Research the content of the NCO creed and evaluate counseling and other forms of NCO guidance without knowing the track of the thesis it is hard to be more concise.

Thank you to everyone who commented or made suggestions. It turned out that they wanted a personal perspective rather than doctrine so O had to go in another direction.