Children of Earth: Day One - S3-E1
Factual error: On the government database, Torchwood is described as being founded by HRH Queen Victoria. As a sovereign, she was actually HM (Her Majesty) not HRH (Her Royal Highness).
Children of Earth: Day Three - S3-E3
Factual error: Frobisher tells the 456 he is the Permanent Secretary of the Home Office of the "United Kingdom and Northern Ireland". It should be the United Kingdom of Great Britain and Northern Ireland. Northern Ireland is part of the UK.
Children of Earth: Day Three - S3-E3
Factual error: Andrew Staines was a junior Scots Guards officer in the 1960s according to the Torchwood database. However, the photograph of him in that era shows him with a general's capbadge.
Chosen answer: As long as Jack's been in charge of it, Torchwood Cardiff has had a different agenda than Torchwood One. Tosh and Owen were there to watch for signs of the 10th Doctor, however, it was the 9th that showed up when the ship crashed in London.
Captain Defenestrator