Law Enforcement Agencies in East Saint Louis, IL IL › St. Clair County Agencies serving the city of East Saint Louis in IL. Agency Types in East Saint Louis Adult Institutions 1 agencies Federal 1 agencies Municipal Police 1 agencies Probation Pretrial 5 agencies All Agencies in East Saint Louis, IL East Saint Louis Police Department St. Clair County SW IL Corrections Center & Work Camp St. Clair County US Marshals Service St. Clair County US Probation & Pretrial Services Office St. Clair County US Probation & Pretrial Services Office St. Clair County US Probation & Pretrial Services Office St. Clair County US Probation & Pretrial Services Office St. Clair County US Probation & Pretrial Services Office St. Clair County