Captain's Mast is the Navy term for Non-judicial Punishment (NJP). This is used when a Sailor is in violation of the Uniform Code of Military Justice (UCMJ). This is only used when other options to correct deficiencies have been unsuccessful or when the violation is fairly egregious (some examples are under-age drinking, drinking and driving, adultery, UA (unauthorized absence), integrity violations (cheating/lying) and assault). The process is involved, has a few steps of review and your Sailor has the right to remain silent, the right to an lawyer and the right to appeal to a higher authority. However, there are no rules of evidence for NJP. The Captain will review the Sailor's entire record before the Mast. When they go to Mast they stand in front of a table in their dress uniform with their Commanding Officer (CO) sitting at the opposite end of the table. Their entire chain of command (including their advisor or Chief) will be posted along the left hand side of the CO. The Captain will ensure that they have been made aware of their rights and the charges leveled against the Sailor. The Captain will then ask the Sailor questions about the incident and then consult the chain of command about the Sailor's abilities, potential and effort. The CO will then make a decision about the Sailor and "award" him punishment. (We use the term award for both positive (medals) and negative (fines) things given by the CO as they are both earned.) The biggest benefit of NJP rather then Court Martial is that the CO is limited on the amount of punishment that he can award.
Firstly, I would like to say that at no point does the Navy give its Sailors only one chance and set them up for failure. Most Mast cases at training commands are based up several violations that the Sailor has shown no interest in correcting. As for the more sever issues that go straight to Mast that I talked about above, the Sailors are trained on those things being wrong and the consequence of there actions on countless occasions including "sea stories" from the staff about themselves or other Sailors. We realize that many of these are 18-19 year olds who still lack maturity and try our best to focus them into the Sailors that we need.
Second, Mast does not end the Sailor's career. It affects it, but the goal is that this will act like a spanking and convince the Sailor that they are doing the wrong thing. During the Restriction and Extra Duty they are constantly trained on military obligations and refocused in a boot camp like style. In addition the Sailor is given whatever aid is needed to help them with their issues (example Drinking and driving they see the command DAPA (Drug and Alcohol Program Advisor) and are referred for whatever treatment is deemed necessary for their problem with alcohol). The best thing you can do for them is encourage them to correct whatever problem caused them to go to Mast. Guide them to try and live within the rules rather then try and cheat the system without getting caught.
Finally, if your Sailor refuses to be a Sailor then chances are he or she will eventually be separated from Naval Service with some form of non-Honorable discharge. Please believe me that if this happens it is because we have exhausted all reasonable efforts to help them or they refused to help themselves (drinking and driving a second time after treatment results in ADSEP automatically). Additionally, we do NOT simply escort them off base and take away their seabag. We give them plane or bus tickets as far off as their home of record; prior to discharge we counseled them on getting a job related skills; we give them whatever treatment they need (counseling/drug or alcohol treatment) and will provide transportation to the airport or bus/train depot as needed. They are adults however and we have no right to contact you their parents if the Sailor does not choose to do so on their own. We counsel them to contact you but as everything else in life it is their choice.
I hope that I have been able to clear up any misconceptions or misunderstandings that are involved with Captain's Mast.