I have three responses to your post:
1. You did not ask a question
2. As many people do, you withhold the most significant fact that might allow some intelligent analysis of your situation: what it was you did that they want to discipline you for.
3. We don't read minds. If you don't want to tell us the problem, please save everyone's time and don't post.
Under certain circumstances, a public employee may be disciplined for conduct done off duty that, while not illegal in the sense it would subject a person to criminal liability, brings discredit to the department.