Q&A: Which is the oldest parliamentary statute still in force?

The oldest statute still in force today is habeas corpus, which ensures that any court of law can demand that any person is brought before it...

This Q&A was first published in the January 2013 issue of BBC History Magazine

This means a prisoner or someone acting on his behalf can always seek redress, so no person can be held unlawfully or without fair trial.
But habeas corpus was not an act of parliament: it was first codified in Magna Carta in 1215, and likely grew out of procedures in place as early as the 11th century. The extant version of the law dates from the amended Magna Carta issued by Edward I in 1297.
The term ‘parliament’ did not arise until November 1236, when Henry III first used it in official records to describe the council of noblemen who advised him. 
Of course, it could be argued that parliament didn’t really begin until 1265, still during Henry III’s reign, when the barons defeated the king and forced him to accept regular meetings that included representatives from the counties and towns. In that case, the answer is the Distress Act of 1267, laid out in several chapters of the Statute of Marlborough. This act made it illegal to seek ‘distresses’, or recompense, for damages anywhere other than a court of law,  thus outlawing the settling of private feuds in the streets. 
Answered by freelance writer Dan Cossins.