--- title: "Catherine A. Dierker | KnowJudges" canonical: "https://knowjudges.com/kyj/judge/catherine-a-dierker-judge-missouri-20th-judicial-circuit-court-mo" page_type: "judge_profile" updated: "2026-10-07" --- # Catherine A. Dierker Missouri 22nd Judicial Circuit Court · Associate Circuit Judge ## Profile - Court: Missouri 22nd Judicial Circuit Court - State: Missouri - Role: Associate Circuit Judge - Service status: active - Last verified: 2026-07-26 ## Summary Official statewide and applicable court procedural guidance applies to this judge. ## Biography ### Professional career - She had been serving as Associate Circuit Judge in the 22nd Judicial Circuit since December 1, 2023, when she was sworn in by her father, retired Judge Robert H. Dierker - Catherine Dierker was appointed on 2026-02-13 as Circuit Judge for Missouri 22nd Judicial Circuit Court - Appointed Circuit Judge by Governor Mike Kehoe on February 13, 2026, succeeding retired Judge David C. Mason - 13, 2026: Appointed Circuit Judge, marking a promotion to the full circuit bench - 1, 2023: Sworn in as Associate Circuit Judge, the first daughter of a St. Louis judge to serve on the same bench - Previously criminal prosecutor for Missouri Attorney General’s Office and St. Louis Circuit Attorney’s Office ### Education - in English Literature — George Washington University — B.A. - in Anglo-Irish Literature and Drama — University College Dublin — M.A. - Washington University School of Law in St. Louis — J.D. ### Additional information - 5, 2024: Retained in her associate judge role by a 57.9% vote in a retention election - She is also a member of the Missouri Bar, U.S. District Court (Eastern & Western Districts of Missouri), Eighth Circuit Court of Appeals, and the St. Louis Lawyers Association ## Before you appear - Read the judge-specific standing order first when one is listed. - Check the docket and case orders for requirements that supersede broader guidance. - Confirm current remote-access and courtroom technology arrangements before the proceeding. ## Courtroom Rules ### media equipment advance approval Scope: statewide Missouri Court Operating Rule 16 requires advance approval for media equipment used for courtroom coverage and allows the judge to control the number and setup of media personnel and equipment. Evidence excerpt: Failure to obtain advance approval for equipment may preclude its use in the proceeding. [Missouri Court Operating Rule 16.04, Technical](https://www.courts.mo.gov/page.jsp?id=354) Source checked: 2026-07-26 ### device use in courtroom Scope: statewide Missouri courtroom device use for media coverage is not generally permitted unless authorized by the operating rule, a local court rule, or the judge presiding in the proceeding. Evidence excerpt: No person may use any device capable of media coverage in a courtroom or court clerk's office unless specifically authorized [Missouri Court Operating Rule 16.04, Technical](https://www.courts.mo.gov/page.jsp?id=354) Source checked: 2026-07-26 ### audio video recording Scope: statewide Missouri allows limited video and audio recording for media coverage under COR 16 technical limits, subject to judicial approval and courtroom controls. Evidence excerpt: Not more than one videographer, using a single device, shall be permitted in the courtroom during a judicial proceeding at any time. [Missouri Court Operating Rule 16.04, Technical](https://www.courts.mo.gov/page.jsp?id=354) Source checked: 2026-07-26 ## Sources - [Official profile](https://www.sos.mo.gov/cmsimages/bluebook/2025-2026/5_Judicial.pdf) - [Official roster](https://www.sos.mo.gov/cmsimages/bluebook/2025-2026/5_Judicial.pdf) - [Missouri Secretary of State Official Manual official judicial roster](https://www.sos.mo.gov/cmsimages/bluebook/2025-2026/5_Judicial.pdf) - [Missouri Court Operating Rule 16.04, Technical](https://www.courts.mo.gov/page.jsp?id=354) - [Governor Kehoe Announces Three Judicial Appointments](https://governor.mo.gov/press-releases/archive/governor-kehoe-announces-three-judicial-appointments) ## JSON-LD ```json { "@context": "https://schema.org", "@graph": [ { "@type": "WebPage", "@id": "https://knowjudges.com/kyj/judge/catherine-a-dierker-judge-missouri-20th-judicial-circuit-court-mo", "url": "https://knowjudges.com/kyj/judge/catherine-a-dierker-judge-missouri-20th-judicial-circuit-court-mo", "name": "Catherine A. 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