Russian Diplomatic Espionage in Italy

After uncovering Russian espionage activities on Italian territory, Italy expelled two Russian diplomats allegedly involved in such activities. The Italian decision, as well as the Russian response, offer a classic example of States’ reaction to acts of non-violent espionage. This comment offers a legal assessment of the events that unfolded in March 2021 and takes into account the implications, in matters concerning espionage, of declarations of persona non grata, diplomatic immunity and, generally, customary international law.