Define the direct effect of primary law.

The effect: 1. Treaties are primary law 2. Van Gen en Loos confirmed that treaties could have direct effect (case concerned the internal market)' 3. There were two competing views before the court: - Dualist: legal rights of private parties could not derive from the treaties, but solely from a legal measure of a MS - Monist: EU law was capable of directly creating individual rights 4. Court favoured monistic view