An investigator is engaged in surveillance for an insurance fraud case. They witness the subject commit a minor criminal offense unrelated to the insurance claim (e.g., shoplifting a small item). What is the most appropriate action?

1. Ignore the offense entirely as it's outside the scope of work.
2. Report the offense directly to the police without informing the client.
3. Immediately intervene and make a citizen's arrest.
4. Document the observation in the surveillance log and report it to the client, but the PI's primary role is not law enforcement.