Members of the European parliament are elected directly by the people, and their mandate is only for work in the European parliament. Most of them have no insider knowledge of what happens in the ministries of individual countries.

To give some numbers: according to Wikipedia[1], about a third of MEPs have previously held positions in country parliaments, and about 10% in country ministries.

[1] http://en.wikipedia.org/wiki/Member_of_the_European_Parliame...