To join the Army as an MP a couple of requirments have to be met. First off just to join the Army you have to score high enough on the ASVAB test, which any Military Branch recruiter can schedule for you, secondly you have to meet the physical requirements. The physical will be administered at your closest Military Entrance Processing station. It is basically an amped up sports physical you may get for football. They do take a blood and urine test also. If you are a female they do take a quick glance to "make sure" everything looks the way it should. Also, if you are on any medication you cannot join, and that is ANY medication. Some meds for depression can disqualify for over a year, which means your doctor has to clear you to not take them and then you have to be off them for a year. Now those two are requirements are just to get into any job in the Army. Now if you want to be an MP you basically have to have no law violations. Or at least nothing over a basic traffic ticket. This is based on my experience. If you ever used marijuana, or any drug for that matter you will not qualify to be an MP. But, remember if you have only used a couple of times and you are clean right now how would your recruiter ever know? So, yes if you are mentally, morally and physically qualified you can get MP in your contract. BUT, it has to be available. What that means is training has to be open for them to get you that job. So, when you sit down to look for that job or training if it isn't there and you are otherwise qualified it may be a long wait to get that position. It can be anywhere from 3 - 6 months for training to open back up.