Tehran Police Uniforms:Why Written In English ?

Todays front page of The Wall Street Journal shows a club-wielding Tehran, Iran policeman beating a man in front of Tehran University. The graffiti on the wall behind the combatants is written in Farsi-the language since the 9th century. Yet on the back of the police officers uniform are the words "Police" written in English not Farsi ! 

Looks like propaganda by the WSJ and others served up for dummies.