After successfully completing a doctorate at Flinders University in South Australia, Philip Dorling joined the Department of Foreign Affairs and Trade in 1992. Initially employed as a historian, he later took a role in policy – in particular being responsible for issues concerning both arms control and non-poliferation. In 1996, Dorling moved to become an advisor to Laurie Brereton, who at the time was serving as the Australian Labor Party's foreign affairs spokesman. He continued in this post until 2001, and while employed in this role Dorling was "especially engaged in policy relating to Indonesia and East Timorese self-determination". While working with Laurie Brereton, on 16 September 2000, (the first day after the opening of the Sydney Olympics), Dorling's home was raided by the Australian Federal Police on allegations he had leaked confidential information about East Timor to the media. Described in The Sydney Morning Herald as a "political witch hunt", the police were searching for copies of approximately 80 documents, although no evidence was found. After leaving Laurie Brereton's office, Dorling spent two years (2002-2003) working as an advisor to Daryl Melham, the Shadow Minister for Justice and Customs. He was then briefly engaged in the TasmanianPremier's department in 2003 before moving to the Australian Capital Territory's Chief Minister's department, where he worked until 2008.
Upon leaving the Chief Minister's department, Dorling was engaged as the National Affairs Correspondent for The Canberra Times. Dorling was, however, once again caught up in controversy when the Australian Federal Police raided Dorling's home on 23 September 2008, after he quoted from classified briefing papers intended for the Australian Minister for Defence, Joel Fitzgibbon. Police reportedly seized "several documents" as a result of their search.