What happens if a soldier avoids a deployment by fleeing to Mexico?

If they are going to break their word and violate their oath, they are going to suffer. The best thing your friend could do would be to go talk to a Chaplain or lawyer who could help them navigate the situation while bringing as little dishonor upon themselves as possible.

It doesn't matter where they run. The only thing that matters is that they are AWOL/UA, and eventually declared a deserter.

My first month as a platoon leader, I got back a Marine who had been a deserter from the platoon for 24 years. He deserted the year before I was born. There was no war, he just didn't want to be a Marine anymore. He had a wife three kids and was the General Manager of a KMart about 30 miles North of Camp Pendleton.

Less than 4 hours after being apprehended in the KMart, he was standing in front of my desk, head shaved, heels locked, serious dumbfounded 1000 yard stare; being informed of his rights. Then next day he plead guilty to desertion. 90 days later he was released from the brig and sent on his way with a BCD. He had no job and I don't know what happened with the marriage, but neither his wife or kids were there to pick him up.

We used to have an occasional Marine go UA while we were deployed on our WestPac cruise. In these cases, we were already deployed on ships, and they would normally go UA in Okinawa or PRI and not come back when we left port. We just left them out there and took no action other than normal reporting such an incident higher up and to local authorities. Unless they were apprehended breaking a local law, local LEOs paid them no mind. They always came back in a month or so when their money ran out and their girlfriends kicked them out. By then they had usually lost 20-30# and looked like something the cat drug in.

Depends on if this country is at war

Should this individual successfully cross the border into Mexico and miss his deployment date, then he should be listed and pursued as "AWOL" ! Should this period of time extent past the 30 day time from, then he should be designated a "deserted" and sought on a criminal military warrant, and yes the Mexican government will gladly return this man to his own country rather than risk an international incident !

First of all, any military member AWOL in a foreign country like Mexico, would be at the mercy of the Mexican government. If this member was without his passport were apprehended, Mexico wouldn't always return him/her to the USA. Mexican jail is no sweet place to be for a "gringo" AWOL military member to be. If the American embassy cuts a deal for that member's release, then that member gets to go back to the USA, face AWOL charges, maybe desertion charges, time in Leavenworth (maybe) and then a dishonorable discharge. Or the judge can send that member's butt to his deployment that he missed. Nah.

I hope he rots in his own he'll full of cowards like him who joined the military in war time only to run and hide when his name came up.
Good riddance.
Bye, Felicia

We had a junior marine go AWOL. This guy was the epitome of a military turd and everyone tried to help him. He disappeared for about 2 weeks then someone from the unit saw him on base. Marines and I am sure other branches don't have much love for those instances. Our CWO-3 sent a few of us out to "retrieve" him. Needless to say we accomplished the mission and he found out the hard way that what he did wasn't a good idea. Besides being in the brig for three months he caught the desertion charge and was dishonorably separated. People should know what their getting into before they sign the papers military is not for everybody. Yet when the commitment is made for better or worse you're now representing America's fighting force and that comes with responsibility as well as repercussions regarding the shirking of that responsibility.

Okay, first off "your friend" needs to understand there is no statute of limitations on desertion PERIOD.
See the Ms. Vicki article that SFC Christopher Taggart posted for a good example. and read on, please:
I was on USS Nashville and we were in the Med on deployment when a deserter was returned to us for judgment. A deserter is always returned to his/her last command if possible in the Navy even if that command is deployed and overseas.

Petty Officer First Class X (that is an E-6 in the Navy FYI) had some "personal problems at home" and the only way he thought he could solve them was to go home immediately. He had used up all his leave and he decided "fuck it, I'll just go and take care of it and be back in a couple of days." Well, Days turned into weeks, into months and then years.

One day he was driving down the road with his wife and kids and was stopped for a speeding ticket. The State Patrol Officer in PA checked and arrested him on the spot for being a deserter, handcuffed him in front of his children and took him away! Brig Chasers were dispatched and within a day he was back in Navy custody and within 2 days after that, he was on a plane to the Med and eventually to Marcelles, France, and USS Nashville. Once on Nashville, a CM was convened, he was convicted and I had the "pleasure" of escorting him and 2 others to Rota, Spain for confinement there, not back in CONUS. He was sentenced to 24 months, BCD, loss of all pay and allowances, and reduction to E-1.

So, What happens if a soldier avoids a deployment by fleeing to Mexico? Can you guess?

Field grade Art-15 or court martial. Admin discharge. They will flag his SSN, if it turns up they could be arrested and tried regardless how much time passes.