Thomson was educated at the state comprehensive Cranbourne Secondary School, in Basingstoke, Hampshire, followed by University College, Oxford.
[citation needed] He has worked on investigations in the UK on Bloody Sunday, the Hillsborough disaster, the 1994 Mull of Kintyre Chinook crash and Rangers F.C.. His current role is chief correspondent and presenter for Channel 4 News, produced by ITN.
He has covered more than twenty wars and conflicts as well as other international issues from climate change and natural disasters to global politics.
In June 2012, Thomson's vehicle, in which he and other journalists were travelling while covering the Syrian uprising, came under fire and took evasive action.
According to Thomson and others present, this was the result of a small group from the Free Syrian Army who attempted to have the team killed in no-man's land by the government forces as a propaganda stunt to discredit Damascus.