Lord Trimble’s challenge: does the backstop violate the Good Friday Agreement?

Trimble’s legal challenge faces some obvious hurdles.

LONDON, ENGLAND - MAY 09: Lord David Trimble waits in in the House of Lords for the arrival of Queen Elizabeth II, and Prince Philip, the Duke of Edinburgh, to conduct the State Opening of Parliament on May 9, 2012 in London, England. Queen Elizabeth II unveiled the coalition government's legislative programme in a speech delivered to Members of Parliament and Peers in The House of Lords. New legislation is expected to be introduced on banking reform, House of Lords reform, changes to public sector pensions and plans for increased internet monitoring. (Photo by Oli Scarff - WPA Pool/Getty Images)

The proposed “backstop” to the Brexit withdrawal agreement is often defended on the grounds that it is necessary in order to uphold the Good Friday Agreement. But does it, rather, do the opposite?

That’s the view of Lord Trimble, who has now said that he plans to bring legal proceedings to this end. He’s one of the architects of the Agreement, although that doesn’t make his view definitive: nationalist parties in Northern Ireland and the Irish government, who were also part of the Good Friday process, have the opposite interpretation. But let’s look at the case he makes.