36 U.S.C. § 200303 — Membership

(a) General. Except where this chapter says otherwise, who can join, and what rights, privileges, and membership classes exist, are set by the corporation's constitution and bylaws. (b) Required Service. The law itself limits membership to male blood relatives of a person who: (1) served at some point between April 12, 1861, and April 9, 1865, as a soldier or sailor in the U.S. Army, Navy, Marine Corps, or Revenue-Cutter Service, or in a state regiment that was called into active service and took orders from U.S. general officers during that period; and (2) was either honorably discharged from that service or died while serving.