Are retirees subject to UCMJ?

Talked to a JAG Lawyer. There are 3 circumstances where Retirees (and even non-retired vets) can face UCMJ:
1. For any crime committed in service where the final disposition was never made, even if the service member left the service 100 years ago. This is for both veterans AND retirees and for both misdemeanors and felonies.
2. If a service is receiving pay FROM THE BRANCH OF SERVICE and commits a felony. This does not extend to VA paid disability. Does not apply to misdemeanour. For example, if a disabled vet/retiree chooses Army/Navy/whatever compensation in a lump sum instead of VA percentage, then they can be tried under UCMJ. The VA has their own policies for handling vets who commit felonies and those policies are backed by federal law, not UCMJ.
3. The obvious one, desertion. I faced this one because I was admin separated from the Navy with an Honorable Discharge but RE4 reenlistment code due to Captain's Mast. A year later I was arrested by local law enforcement and turned over to NCIS. It was just a mixup of paperwork and got sorted out just fine, but it prompted me to get a lawyer. What prompted it was I had orders to FMTB but they never got the memo of my separation and put out a warrant for my arrest lol.

Side Note: While Article 2 does not mention nonretired vets, it has been confirmed to apply to them. However compensation is so rare for nonretired vets. The GI Bill is a VA Benefit, not a military one. The military has no control over the GI Bill except for what discharge they give, which affects eligibility. So a vet who only receives GI Bill and VA Home Loan do not fall under article 2.

I remember a case in Germany where a retired Sergeant Major worked at Toyota car dealership and was helping his customers defraud the US government. He was given non juridical punishment/ article 15, reduction in pay.

Only if the crime was committed while suspected was in the military, crime committed on military property and statue of limitations is not up.

A “retirement” check is, in reality, a “retainer” check giving the govt the right to re-call anytime. However, I don’t think this would happen except in extremely rare cases.

If a military person committed a crime, such as murder, while within military jurisdiction (see below), but the crime wasn't discovered (or evidence available) until after that person retired, then I can see it happening. There's a couple Constitutional caveats that would determine if it's tried under UCMJ or not.
Did the crime, punishable under UCMJ, take place where U.S. courts do not have jurisdiction, during an overseas military operation, and on a military installation? Pay particular attention to "when in actual service in time of war or public danger," within the 5th Amendment, and "public trial by an impartial jury of the state and district wherein the crime shall have been committed," part of the 6th Amendment.
It seems portions of Article 2, UCMJ, are in direct violation of the U.S. Constitution. Someone may need to check their hubris.

I have never heard of, nor do I believe, that you can be charged with a UCMJ offense as a civilian retiree except for offenses committed while on active duty (in which case they reactivate you and then charge you.) If that were true, why does the person need to be reactivated - why not charge them as a civilian? I see the words but have trouble believing it.

A retiree is basically defined as one that has put in at least 20 and in receipt of a Govt retirement check. However, that “retirement” check is not retirement. It’s a “retainer” check. Simply put, once you retire, the Govt retains the right to ownership. That’s you. FOR LIFE.

Totally non-pulsed. If you messed up so much that the military takes notice, embrace the suck! Gunny J. OUT!

Ha! Totally non-pulsed about this. Retired in 2003 and would have to really "break bad" to ever be subjected to the UCMJ! Semper Fi.

Retired personnel can be brought back to active duty to answer to conduct that happened in active duty. But conduct that happens after full retirement ( if you are on final leave, you are subject to UCMJ) is not. Just like Pay and benefits your responsibility goes away! You are another civilian!