Complex sentence: The Russian Supreme Court has ruled the propiska to be unconstitutional on several occasions since the fall of communism and it is considered by human rights organizations to be in direct violation of the Russian constitution, which guarantees the freedom of movement.
Split into simpler sentences: The Russian Supreme Court has ruled the propiska to be un-constitutional on several occasions since the fall of communism. However, this is considered by human rights organizations to be in direct violation of the Russian constitution which guarantees the freedom of movement.