Illinois Certification Of arresting Officer Regarding Probable Cause For Detention Of Person arrested Without Warrant is a form that an arresting officer in the state of Illinois must fill out in order to legally detain a person who has been arrested without a warrant. This form is used to certify that the arresting officer had probable cause to believe that the person was committing a crime at the time of the arrest. The form requires the arresting officer to list the facts and circumstances that provided probable cause for the arrest as well as any other relevant information. There are two types of Illinois Certification Of arresting Officer Regarding Probable Cause For Detention Of Person arrested Without Warrant: a Standard Certificate and an Emergency Certificate. The Standard Certificate is used when the arresting officer has had time to consider the facts and circumstances that constitute probable cause, while the Emergency Certificate is used in emergency situations when the arresting officer must act quickly.