Because of his heavy involvement in crimes related to Srebrenica, his colleagues nicknamed McCloskey “Mr. Srebrenica”.

Peter McCloskey began working at the ICTY on 1 October 1996. He was assigned the Srebrenica case only two days later, and worked on it for a total of 21 years, until the first instance verdict in the Mladić case was handed down. This was the Tribunal’s penultimate judgment before its closure in 2017. McCloskey worked on all cases related to proving genocide and other crimes committed in Srebrenica in 1995, including those against Ratko Mladić, Radovan Karadžić, Zdravko Tolimir, Dragan Obrenović, Momir Nikolić, Zdravko Tolimir, Dragan Obrenović, Vidoje Blagojević, Dragan Jokić, Vujadin Popović, Ljubiša Beara, Dragan Nikolić, Ljubomir Borovčanin, Radivoj Miletić, Milan Gvera, and Vinko Pandurević, all of whom were found guilty by the ICTY.

ICTY prosecutors and investigators marked the end of work ICTY with a Death March from Potočari to Nezuk. Participants of the March in front of the Srebrenica- Potocari Memorial Center before departure from Potočari to Nezuk on May 2017

"My 21 years at the ICTY has been the opportunity and privilege of a lifetime, and I count myself one of the luckiest persons on the planet to be involved in this work."

"My father’s work as an attorney, congressman, environmentalist, baseball coach and much more played a crucial role in my desire to spend my career in public service, and he has let me know how proud he is of my achievements."

"The effort put in to the Srebrenica investigation and resulting trials was unique, in that the core team members began the investigation together and worked around the clock together through the end of the Krstić trial and well beyond. I was lucky enough to be part of the initial investigation, indictments and all the Srebrenica trials through the closing of the ICTY. The core team of myself, chief investigator Jean-René Ruez, military analyst Richard Butler, analyst Stefanie Frease and analyst and interpreter Adisa Karamuratović, along with several other superb investigators, was perhaps the strongest group of people assembled for any investigation in any tribunal. We worked together for several years, building a case that revealed in great detail the enormity of the crime and those most responsible for it. The convictions in all the resulting trials provides the historical record of the investigation, as well as the horrendous crimes it exposed."