A more thorough explanation:

Definition: A prover is a person who has been accused of a serious crime and is trying to get a pardon by admitting their guilt and revealing the names of others involved in the crime.

Example: In the past, a prover might have been someone who was accused of being a thief. They might have told the authorities who else was involved in the theft in order to get a lighter sentence or avoid punishment altogether.

Explanation: The example illustrates how a prover would confess to their own crime and provide information about others involved in the crime. This was often done in the hopes of receiving a pardon or reduced sentence. The term "prover" is not commonly used today, but it was a common practice in the past.