The International Criminal Police Organization, or INTERPOL, is an intergovernmental organization facilitating international police cooperation.
When Skye hacked the NSA satellites for video on the release of the prisoners from the Fridge, Agent Grant Ward killed Agent Eric Koenig and stopped the feed to conceal his involvement. When Skye returned and asked about Koening's location, Ward told her that he was sending the info to NATO, the CIA and Interpol.
Following the murder of the Russian government officials General Androvich, Yuri Krupin, and Anton Petrov, Lance Hunter and Bobbi Morse were caught. President Matthew Ellis got the Interpol to interrogate them. Duval questioned them about the assassinations, but ultimately let them go after he was convinced they were not in S.H.I.E.L.D..