Interpellation d’un prédateur sexuel près d’un parc pour enfants

What does “en flag” mean in French?

“En flag” is French police and street slang for caught in the act — red-handed. It’s a clipped form of “en flagrant délit,” the legal term for an offence witnessed as it happens or just after. Officers say someone was nabbed “en flag” the way English says “caught red-handed,” with the same charged, on-the-spot urgency.

The full phrase descends from Latin “in flagrante delicto,” literally “while the crime is blazing.” In French law “la flagrance” unlocks special powers — police can act on the spot without prior authorisation, generally within 24 hours of the offence. The slang “flag” has been around since the 1930s and is now standard in crime reporting and cop dramas.