Looking for any information on Deputy U.S. Marshal Anderson Keen sworn in in 1870 assigned to OK. Does anyone know of any books or info referencing him?

Keen, Anderson was commissioned on July 24, 1890, in the Western District at Ft. Smith, Arkansas, serving under Marshal Jacob Yoes. (Ft. Smith Federal Court Employee Database) (Ft. Smith Oaths of Office) (Ft. Smith Historical List)

Does anyone have information relating to the charges of murder levied against Anderson Keene (a/k/a Keene Anderson, a/k/a Levi Laughlin) in about 1890? Could this have been related to a killing in connection with his duties? The following is found in the National Archives for Ft. Smith Criminal files:

Last Keene
First Anderson
Charge Murder
Year 1890
Jacket 517
Aka
Etal E
Unk K500

Last Laughlin
First Levi
Charge Murder
Year 1890
Jacket 517
Aka Keene, Anderson
Etal
Unk L245

Thank you in advance for any information you can provide on this Marshal.

You will have to order a copy of that criminal case file from the National Archives at Fort Worth Texas. It is $15.00 per file up to 25 pages and then an additional fee after that amount has been reached.

Good luck