The European Court of Justice's assault on discriminatory tax barriers is being felt across the EU. But the government has more to fear than most from the growing influence of the ECJ on European tax laws.

In part, this is because the UK raises more of its tax revenues from corporation tax than most other countries. But it is also because the design of the UK's tax regime makes it unusually vulnerable to legal challenges under the Treaty of Rome, which prohibits discrimination against other EU nationals.