Sorry Sgt. a service member can't sue the government. or a gocvernment official (i.e. you commander)--they are immune from suit on several theories.
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You cannot sue the military directly.
There are quite a lot of steps that are missing from the above on how they got to a separation.
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You may not be able to sue the government but there may be other remedies applicable. AR 635-200, Chapter 14-12c cover 'serious offenses.' At 17 and 1/2 you probably had an administrative separation board. Under 14-12c, the board members do not have to examine your rehabilitation potential. On the other hand, there may be protections for Soldiers who are very close to retirement - this would require further research. Assuming there have been major flaws in the separation board, or chapter 14 processing, you could seek to be restored to Active Duty.
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