Although institutions are often associated with a physical representative (like the supreme court building), the essence of an institution is a set of expectations and - that shape the - in which -.

I believe the answer is: decisions are made.

In order to ensure all government-related process run smoothly, there are some institutions that have the independence to make their own decision (regardless the preference of higher government officials)

This type of independence is especially needed in court where the judge need to be as fair as possible.