WHO, WHAT, WHY?
The Magazine answers...
There are plans afoot to change the laws on treason in the UK, with a commission on citizenship led by Lord Goldsmith recommending reform, but what is the law ?
There is an awful lot of statute law in the UK that deals with treason.
But the most important part was first passed in England in 1351. And it is perhaps one of the few pieces of 14th Century legislation to be regularly discussed in the 21st Century.
The essence of a law from 1351 remains in place
In recent times no-one's really known how to change it
The original law said: "When a Man doth compass or imagine the Death of our Lord the King, or of our Lady his Queen or of their eldest Son and Heir; or if a Man do violate the King's Companion, or the King's eldest Daughter unmarried, or the Wife the King's eldest Son and Heir; or if a Man do levy War against our Lord the King in his Realm, or be adherent to the King's Enemies in his Realm, giving to them Aid and Comfort in the Realm."
Or rather what the law actually said was in Norman French, but put succinctly in English, you can't kill, conspire against or wage war against the king and his family. You also can't have sex with his wife, heir's wife or his unmarried eldest daughter. And the act goes on to rule out actions against the chancellor, treasurer and various categories of senior judge.
Treason existed before the 1351 act, but this was the first attempt to set parameters for it, says legal historian Prof Michael Lobban, of Queen Mary, University of London.
"We did have treason before but it wasn't very well defined. There was concern that the crown could manipulate a trial. They wanted to give a precise definition to it."
And this precise definition in England and Wales - and from 1708 in Scotland - has not changed a great deal over the years, despite a host of other treason acts.
WHO, WHAT, WHY?
A regular part of the BBC News Magazine, Who, What, Why? aims to answer some of the questions behind the headlines
Some of the acts that have come since have been to change the punishment. The 1814 act decreased to hanging a punishment that was traditionally described thus:
"[To] be drawn on a hurdle to the place of execution and there be hanged by the neck, but not until they are dead, but that they should be taken down again, and that when they are yet alive their bowels should be taken out and burnt before their faces, and that afterwards their heads should be severed from their bodies, and their bodies be divided into four quarters, and their heads and quarters to be at the King's disposal."
It took until 1998 and the Crime and Disorder Act to get the punishment further downgraded to life imprisonment.
Treason legislation has often been caught in political eddies. After Henry VII ascended the English throne at the Battle of Bosworth in 1485, he set the date of the start of his reign earlier than the battle and threatened the supporters of the defeated Richard III with treason. Men who had defended the "rightful" king were being accused of offences against the usurping king.
So in 1495, a treason act allowed a defence for those in this situation.
And the tumultuous political times of 1848 led to a treason act that dealt with people who advocated constitutional change rather than actual harm of the monarch.
The Treason Felony Act 1848 makes it an offence to deprive or depose the Queen from her established constitutional position - and to publish any writing or printing advocating such change.
"It was aimed at Chartists and Irish radicals," says Prof Lobban.
Six years earlier in 1842, the law on attempts to "injure or alarm the sovereign" had been strengthened, with specific reference to the use of firearms, following an assassination attempt on Queen Victoria. This law was used in 1981 to prosecute Marcus Sarjeant after he fired blank cartridges in the vicinity of the Queen. He was jailed for five years.
One thing that can be said about the 1351 Treason Act and its successors is that they have been debated more in the late 20th and early 21st Century than they have ever been used for actual prosecutions.
1351: Defines offence
1495: Allows defence
1695: Regulates trials
1702: Bans hindering succession
1708: English/Scottish law harmonised
1814: Ends disembowelling etc
1842: Deals with firearms, attempts to alarm monarch
1848: Deals with radical agitation
1998: Crime act ends death penalty
All acts still in force
It has been suggested Britons fighting for the Taleban or radical Islamist preachers could be charged with treason, while the Guardian newspaper has campaigned for the repeal of parts of the law. But all of the above legislation remains in force, and a clear starting point for an overhaul may be an achievement in itself.
"Successive governments have recognised that there is a case for reviewing what is an extremely antiquated part of the law," says a spokeswoman for the Ministry of Justice.
"Given that in modern practice the law is very rarely used, and there are no concrete proposals as a starting point for reform, the government has not been able to give priority to work in this area which would be at the expense of more pressing reforms."