This encompasses all U.S. jurisdictions, including state and local courts. If the imprisonment or fines are later overturned, they still count. However, if a higher court issues a stay before the enforcement of penalties, it does not count. Excluded are politically motivated punishments unrelated to the journalist's work. The scope includes actions related to the gathering, publishing, or reporting of news.
Here's a list of incidents that would count, but note that the reason for the jail time or fine does not have to be failing to disclose sources: https://www.rcfp.org/jailed-fined-journalists-confidential-sources/
If a journalist is arrested for X, spends Y days in jail, then is released with no charges filed by the DA, would that count as jail time / imprisonment?
What about sanctions that are neither fines nor imprisonments (e.g. restraining orders)?
@LukasDay this question is only about fines and imprisonment, so a restraining order would not count