This Is Not Okay [UPDATED]
No – law enforcement officers should never, under any circumstances, impersonate a journalist.
NEVER.
This action puts all journalists at risk as it implants the idea that anyone claiming to be a journalist could be a law enforcement officer and that opens them up to a significant level of danger, particularly if they cover controversial or difficult subjects.
How serious is the issue? The kidnapping and murder of Daniel Pearl in 2002 may have been due to suspicions that he was a CIA agent.