Regulation check

MARINE INVESTIGATOR BADGES AND CREDENTIALS reads like a Personnel & Career question — these are the publications that govern it in each branch:

PublicationBranchTitleDateStatus
MCO 1020.34HMarine CorpsMARINE CORPS UNIFORM REGULATIONS2018-05-01Current
Looking for an actual answer, not just the pub? Ask it as a question — free, and it quotes the regulation text where indexed.
Numbers match loosely — “ar670”, “AR 670-1”, and “670-1” all find the same pub. Every result shows its live status from the official catalog.