Filibusters are a provision in the United States’ Senate by means of which senators can block a measure by preventing it from coming to vote. The latest episode of television satire show Last Week Tonight with John Oliver traces the history of the provision and its impact on the legislations in the country.

The word filibuster is derived from the Dutch word for freebooter which means pirate. According to the host of the show John Oliver, the filibuster has become an “overused tool of obstruction”. Interestingly, no one knows why it exists. Some researchers have even claimed that it was designed by mistake. The first time that a filibuster was used was in 1837.