Thank you for your question.
What you did was illegal because you fraudulently used his information to register on-line with the insurance company's website. I understand that you had a good motive to do that, but you violated several laws by doing that, but it likely does not include HIPAA
HIPAA prohibits the unauthorized disclosure
of medical records (including health insurance information) by covered entities. A health care provider such as yourself prohibits disclosure by you when you gain access to the information through certain transactions. The way you gains access was not through a transaction.
Rather, you fraudulently used your ex's identity.
So, in short, you do have potential criminal and civil liability
which could end up affecting your nursing license. If the incident were reported to the state board, it does not trigger any sort of automatic penalty but would bring up the possibility for discipline.
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