ELECTED to represent their community in Parliament, MPs are used to walking the corridors of power - not languishing in a prison cell.
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But even politicians previously viewed as pillars of the community can fall on their swords through pride, greed or dishonesty and end up on the wrong side of the law.
Throughout history a scattering have endured the disgrace of serving time as a convicted criminal, with perjury and fraud for personal or financial gain top of the list of offences.
In an early sign of what was to come, 18th century Whig statesman and future prime minister Robert Walpole was accused of corruption and imprisoned in the Tower of London for six months in 1712.
More recently, the high-profile downfalls of Lord Archer and Jonathan Aitken thrust the question of whether politicians could ever be trusted into the spotlight.
Aitken, who was Conservative MP for Thanet East and South Thanet from 1974 until 1997, was jailed for 18 months in June 1999 for perjury after admitting he told a lie on oath in a libel action.
He later described how he turned to God while behind bars at Belmarsh and helped less literate inmates with his "wonderful joined-up writing".
Also swapping the hallowed halls of Westminster for less salubrious surroundings was fellow Tory Lord Archer.
The novelist and former MP was sentenced to four years in prison in July 2001 for perjury and perverting the course of justice.
The jury at his trial found he had lied under oath during his 1987 libel case against the Daily Star over allegations he had had sex with a prostitute.
Starting at Belmarsh, he was subsequently moved to other prisons, ending at Hollesley Bay open prison in Suffolk by the time of his release in September 2003.
Wormwood Scrubs was the destination for another Tory - Peter Baker, who represented Norfolk South.
He was convicted of forgery and fraud and sentenced to seven years' imprisonment in 1954 after forging signatures on letters purporting to guarantee debts when his companies ran into financial difficulties.
But it has not just been the Conservative Party in the limelight.
A memorable case involved John Stonehouse, former Labour MP for Walsall North, who was sent to prison after being found living in Australia under a false name having apparently faked his own death.
He was feared drowned after vanishing on a business trip to Miami in 1974.
But his plan to set up a new life on the other side of the world with his former secretary ended when married Stonehouse was deported to Britain.
In August 1976, he was convicted and sentenced to seven years in prison for theft, fraud and deception.
The charges related to a string of fraudulent businesses set up before his disappearance.
Stonehouse suffered three heart attacks while in prison and was released in 1979. He died in 1988 aged 62.
For another Labour MP-turned-lag, the crime was a matter of principle.
Liverpudlian left-wing poll tax rebel Terry Fields went to prison for 60 days in 1991 rather than pay his community charge bill.