Is it possible to join the marines with a suspended sentences or on probation?
The likely answer is no.
1. You will have to get permission from your probation officer if on probation, to leave the state.
2. You have a conviction, so that in itself is likely to be a bar.
3. You are still serving your sentence and the Marines don't want someone who might get arrested and dragged back to CA after putting the time, effort, and money into training.
Right now the military is undergoing a steep personnel downsizing. That means they are being much more picky about the people they accept. Because of the economy there is a larger pool of applicants, so they have more to choose from.
I doubt the Army would accept you for the same reasons as above.
Concur with Attorney Cave.
Recommend you sit down with a recuriter in your locale, and let him/her describe the battle-space and what you'd have to do to qualify for enlistment. However, I would estimate an enlistment on the circumstances you describe as 0%.--But its been 20 years since I was a recruiter--go see yours and make sure.
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