Why the government may well be defeated on the customs union

Parliamentary votes are often important and sometimes uncertain. However, seldom has a decision been simultaneously so important and so uncertain as the one that MPs look likely to face in a few weeks’ time on the European Union’s customs union.

The government wants the UK to end up with complete freedom to decide how to regulate British businesses and trade with the rest of the world. This means having nothing to do with the customs union. All the opposition parties…