Caught a con is an expression used to describe the act of apprehending a criminal. It is often used in police and law enforcement circles to refer to the successful capture of a suspect. The term is derived from the phrase 'caught a con artist, ' which is used to describe someone who has been caught committing a crime. The term can also be used to describe the apprehension of any type of criminal, including those involved in fraud, theft, or other illegal activities.