A more thorough explanation:

The Court of Star Chamber was a court in England that had broad civil and criminal jurisdiction at the king's discretion. It was known for its secretive, arbitrary, and oppressive procedures, which included compulsory self-incrimination, inquisitorial investigation, and the absence of juries. The court was abolished in 1641 because of its abuses of power.

For example, if someone was accused of a crime, they could be forced to testify against themselves, even if they were innocent. The court also used inquisitorial investigation, which means they would investigate the accused person without their knowledge or consent. This made it easy for the court to find someone guilty, even if they were innocent.

The term "Star Chamber" is sometimes used to describe any secretive, arbitrary, or oppressive tribunal or proceeding.