Mr Clarke has a reputation for tough talking
Charles Clarke may have been thrust into his most serious crisis yet as home secretary, with the revelation that 1,023 foreign prisoners had been freed without being considered for deportation.
He says he will not resign over the issue and has already come through some rough rides since becoming a minister.
Although he has only been an MP since 1997, Mr Clarke has been close to the heart of power in the Labour Party since the 1980s.
The son of a senior civil servant, Mr Clarke was privately educated at Highgate School before going on to Cambridge University, where he studied maths and economics.
He was Neil Kinnock's chief-of-staff from 1983 to 1992 and had a hand in the former party leader's conference speech attacking the Militant wing's administration of Liverpool.
He had previously served as president of the National Union of Students, a well-trodden path to the "grown-up" world of Labour politics at Westminster.
Later, as Labour's party chairman, Mr Clarke proved his loyalty to New Labour, by ruffling feathers within party and union ranks.
THE HOME OFFICE
The Home Office employs almost 70,000 people across England and Wales
Its remit includes crime, policing and justice, drugs, terrorism, immigration, community and race relations
The department also collects statistics in areas like crime and immigration
It carries out scientific projects to support its work - eg, looking at biometrics for ID cards
He has a reputation as a tough-talking political "bruiser" - which was not diminished by his time as education secretary, between 2002 and 2004.
He pushed the Higher Education Bill - with its controversial plans for variable tuition fees - through the Commons in the face of widespread Labour backbench opposition.
He also pointedly snubbed the biggest teachers' union, the NUT, by declaring in 2003 that no education ministers would attend its annual conference.
Delegates had "seriously damaged" the image of the teaching profession, he said, and he again turned down an invitation to speak at the union's conference the following year.
Mr Clarke - who is married with two sons - was tipped for office from the moment he was elected as MP for Norwich South in 1997, despite a few off-message wobbles.
He made clear his opposition to cuts in lone-parent benefits (although he supported it in the voting lobbies) and he called for a fully elected second chamber.
After a year at the education department, he became a minister of state at the Home Office before the 2001 general election.
But he only gained high public prominence when he was moved to the newly created post of Labour chairman, with his salary paid from party funds.
This caused great controversy, since constitutionally Labour already had its own elected party chairman.
In the role he often served as a general media trouble-shooter for the party.
But he has also exhibited a tendency for straight talking which has proved too blunt for some at times.
He accused Prince Charles of being "old fashioned and out of time" for views he expressed on the education system.
Mr Clarke's appointment as home secretary in 2004 put him in charge of the government's top priority - security.
He immediately indicated he would carry on with predecessor David Blunkett's policies on national ID cards and his uncompromising stance on asylum and immigration.
Mr Clarke is keen on technological solutions to terrorism and fraud
It has been a busy period on both fronts for Mr Clarke.
From the 7 July bombings in London last year emerged the Terrorism Bill, which became law this month despite sustained opposition from some quarters including the House of Lords, rebel Labour MPs, opposition parties and civil liberties campaigners.
The government was defeated on one part of the proposals - to extend the maximum period for detention of a terrorist suspect without charge to 90 days - but the law will make it illegal to glorify terrorism, distribute terrorist publications and plan a terrorist act.
Mr Clarke has faced a similar fight with the House of Lords and others over the introduction of ID cards.
Last month MPs agreed a compromise to clear the way for the compulsory introduction of the cards, after the Lords repeatedly blocked the scheme.
Critics say identity cards interfere with civil liberties, are too expensive and will do little to tackle problems like terrorism.
Just a day before the most recent controversy about foreign criminals hit the headlines Mr Clarke took a swipe at the British media, accusing them of perpetuating "myths" that his law and order agenda is an attack on human rights and civil liberties.