Toole was born in Bristol, England, on 19 April 1971. She studied theology and religious studies at the University of Bristol and then went on to complete a postgraduate diploma in journalism at City University London.
After university, Tooley began her career as a journalist with the BBC in 1996. She worked as a reporter and producer for BBC News and Current Affairs for several years before becoming a presenter in 2003.
Toole has presented a variety of BBC News programs, including the BBC News at Six, the BBC News at Ten, Breakfast, and the World News Today. She has also reported from around the world, covering major stories such as the September 11 attacks, the 2003 Iraq War, and the 2011 London riots.
In addition to her work for BBC News, Tooley has also presented several documentaries for the BBC. These include the award-winning Exposure: Life in a Day (2010), Syria's Forgotten Refugees (2014), and The Fight Against FGM (2016).
Toole is also the author of two books, The Secret History of the World's Biggest Art Heist (2014) and We Own This Town: A Biography of the Essex Girls (2020).
In 2019, Tooley was awarded the OBE (Officer of the Order of the British Empire) for her services to journalism.
She is married to fellow BBC journalist John Humphrys and has two children.