The Uniform Code of Military Justice (UCMJ) is considerably stricter than ordinary civilian laws are.
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2.
Partly because of the subsequent criticism of that trial, the Court said, the UCMJ was specifically expanded to cover those accused of war crimes.
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3.
OTH's (other-than-honorable discharges) are given to Marines who grossly violate the UCMJ (Uniform Code of Military Justice), as in drug use, excessive DUI's, adultery, etc.