No one should be altering the time clock. I am not sure how they are manipulating the clock in this fashion. Have you talked with the manager or the tribal legal counsel?
The information provided in this answer does not create an attorney-client relationship. If you are interested in his legal services, feel free to call Chris at (303) 409-7635 at his law office in the Denver Tech Center. All initial consultations are free of charge.
Working more than 8 hours in a shift does not necessarily create a potential claim for overtime. Working more than 40 hours in a work week may create a claim for overtime pay, if you are not exempt from overtime. The Fair Labor Standards Act covers overtime claims and has been applied to tribal employers by some courts.
Disclaimer - This communication in no way offers legal advice, and in no way creates an attorney-client relationship. This communication is only intended to provide general information and should be used only as a starting point for addressing your legal issues. This communication is not a substitute for an in-person or telephone consultation with an attorney licensed to practice in your jurisdiction about your specific legal issue, and you should not rely upon such Legal Information.