The Commission (a vast body of appointees controlled totally by just one man) is the only EU institution that can actually initiate changes to the law. Every other body merely gets to slow it down. This means that if something is on the Commission's agenda, it gets proposed, and if the Commission disagrees, the views of the other institutions are worth nothing.
This setup is very clever because it allows the EU to look superficially democratic without actually being so. Look at all the people saying "write to your MEP" on this thread. It's useless, because of the following process:
1. The European "Parliament" cannot initiate changes to the law (i.e. it's not really a parliament). It can ask the Commission to do it on the Parliament's behalf, but the Commission can say no or propose something different.
2. Therefore, political parties in the EP don't have any real policies. They can't: creating a political party that e.g. campaigns for better immigration control is meaningless in the EU because the Commission will just say no.
3. Therefore, the sort of people who go to sit in the EP and try to win EP elections are basically yes-men, people so enthralled with the whole concept of the EU they just want to be a part of it in some small way, along with a small collection of people who are there only to troll and try to get their country to leave at the EU's expense, like Nigel Farage and Marine Le Pen.
The entire system is designed to LOOK like a democratic government but without ever having to respond to what voters actually want.
