[mschwar99]

The 5th covers several rights of a person accused of a crime. In this context they are referring to the amendment's protection against self incrimination: "nor shall be compelled in any criminal case to be a witness against himself."

A person has the right to decline to answer questions if they believe that their answers could be used against them as evidence of a criminal act. This particular proceeding is civil rather than criminal so its outcome can't result in any criminal convictions. However, if he were later to be charged with a crime and tried in a criminal court any testimony he gave in this civil action could be used against him as evidence in the criminal trial.