The European Parliament has gained more power over the years to improve democracy in the European Union. The latest treaty, the Lisbon Treaty, gave the Parliament even more influence in decision-making. This study looks at how the Parliament helps make decisions on things like choosing the Commission, expanding the EU, and creating laws. It also examines how the Parliament works with other EU institutions and handles conflicts. The study suggests that the Parliament can now impact decisions and actors in a way it couldn't before the Lisbon Treaty, which has big effects on how democracy works in the EU.