Since we cannot determine your place of residence, I'll assume you do not know of 'At-Will-Employment'.
In Indiana (and many other States), employment is 'At Will' which basically boils down to this: You or your employer may terminate the employee/employer relationship at will, with no notice, for any reason OR NO REASON AT ALL.
Legally, they can terminate your employment at anytime.
Only if you can PROVE that you were terminate due to a federally protected status (race/sex/religion/etc...) do you have any legal ground whatsoever.
Personally, I'd have to REALLY LOVE that company and the job to put up with accusations and a lack of trust that's being displayed.
This is definitely not the type of behavior that they would accept from you...