Much of the current focus in parliament is on whether Theresa May should be required to produce a plan setting out her key Brexit objectives. This is quite right. What, indeed, is the plan? Without a good one, it would be foolhardy to embark on such a risky enterprise.
But MPs and peers should focus as much on the end of the process as the beginning. Specifically, they should insist on being able to force a change of course if they don’t like the divorce terms – or if May fails to produce any deal at all.
So long as the prime minister is able to negotiate a withdrawal agreement in the two years provided for under Article 50, parliament will have to give its consent. After all, the agreement will presumably be a treaty – and MPs have the power to stop the government ratifying treaties.
A further referendum may also be required at this point. Under the European Union Act 2011, which created the so-called “referendum lock”, a plebiscite is required before any treaty that amends or replaces the existing EU treaties can be ratified. If the voters rejected the deal, we would then stay in the EU.
One snag is that May could come back with an agreement so late in the day that parliament would have little choice but to let the prime minister ratify it – say if she triggers Article 50 in March 2017 and returns with a deal in February 2019.
Such eleventh-hour brinkmanship would also mean there wasn’t time to hold a referendum. The last referendum lasted over two months. Even if a plebiscite was held, it could take place after we had already quit the EU, making its result pretty pointless.
Another risk is that May is unable to negotiate any deal in the time available. Maybe the discussions would get so fraught that one or other side would walk out. Maybe the talks would drag on without conclusion. Since there wouldn’t be an agreement, there wouldn’t be any need to get parliament’s consent – or hold a referendum.
Neither outcome is remotely satisfactory. Parliament could be bounced into agreeing a deal that wasn’t any good because the alternative of flouncing out of the EU without any agreement was too horrible to contemplate. Alternatively, we might actually quit without a deal – a scenario that’s likely to cause huge economic damage.
But MPs and peers can and should guard against these risks. They could set a deadline by which she must bring back the final withdrawal agreement so it can be debated properly. They could also say that, if the prime minister cannot produce a deal by the specified deadline, she must persuade parliament to renew her negotiating mandate.
Insisting on such a process at the end of the Brexit talks will mean May is subject to appropriate democratic checks rather than given a blank cheque.
Hugo Dixon is co-founder of CommonGround as well as editor-in-chief of InFacts. You can sign up as a supporter here.
