| Amy Zacharias | 4th Judicial District Court | – |
| Ernest J. Zack | Superior Court of California, County of Los Angeles | 1966–1978 |
| Hayden Adam Zacky | Superior Court of California, County of Los Angeles | 2006– |
| David L. Zagaja | Connecticut Superior Court | – |
| James Block Zagel | N.D. Illinois | 1987–2023 |
| Bruce B. Zager | Iowa | 2011 |
| Colleen D. Zahn | Idaho | 2021– |
| Brian K. Zahra | Mich. | 2011– |
| Jay C. Zainey | E.D. Louisiana | 2002– |
| John P. Zakowski | Brown County Circuit Court | – |
| Daniel J. Zalla | Campbell Circuit Court | – |
| Yonatan Zamir | Connecticut Superior Court | – |
| Robert Carmine Zampano | D. Connecticut | 1964–1994 |
| George N. Zanic | Court of Common Pleas of Huntingdon County | – |
| Rohanee April Zapanta | Superior Court of California, County of San Diego | 2018– |
| Frank R. Zapata | D. Arizona | 1996– |
| Stephen A. Zappala | Pa. | 1983–2002 |
| Shirin I Zarabi | New York City Criminal Court, New York County | – |
| Ralph Zarefsky | C.D. California | 1997–2015 |
| Peter T. Zarella | Conn. | 2001 |
| Peter T. Zarella | Conn. App. Ct. | 1999–2015 |
| Robert N. Zarick | Superior Court of California, County of Sacramento | 1980–1984 |
| Levi S. Zaslow | Circuit Court for Baltimore City | – |
| Lawrence J. Zastrow | S.D. | 1976–1979 |
| Lawrence Paul Zatkoff | E.D. Michigan | 1986–2015 |
| Joseph J Zavaglia | Onondaga County Family Court | – |
| Joseph Carmine Zavatt | E.D. New York | 1957–1985 |
| Joseph A Zayas | New York Supreme Court, 11th Judicial District | – |
| Theodore C. Zayner | Superior Court of California, County of Santa Clara | 2010–2019 |
| Mara Zazzali-Hogan | Superior Court of New Jersey, Monmouth Vicinage | – |
| James Ronald Zazzali | N.J. | 2000–2007 |
| John Zebrowski | Cal. Ct. App. | 1986–1999 |
| Marilyn Pestarino Zecher | Superior Court of California, County of Santa Clara | 1975–1994 |
| Vanessa Ann Zecher | Superior Court of California, County of Santa Clara | 2011– |
| Thomas David Zeff | Superior Court of California, County of Stanislaus | 2007– |
| Daniel Zeke Zeidler | Superior Court of California, County of Los Angeles | 2005– |
| Michael D. Zell | Portage County Circuit Court | – |
| Jeffrey S Zellan | New York City Civil Court, New York County | – |
| Howard A. Zeller | N.Y. App. Div. | 1954– |
| Paul E. Zellerbach | Superior Court of California, County of Riverside | 2000–2011 |
| Jacob Zelmanovitz | New York City Civil Court, Kings County | – |
| Laurie D. Zelon | Cal. Ct. App. | 2000–2020 |
| Nancy Ellen Zeltzer | Superior Court of California, County of Orange | 2014– |
| David Zenoff | Nev. | 1966–1976 |
| George N. Zenovich | Cal. Ct. App. | 1979–1984 |
| David M. Zent | Allen Superior Court | – |
| Carrie Ajimura Zepeda | Superior Court of California, County of Santa Clara | 2003– |
| Francine Zepeda | Superior Court of California, County of Fresno | 2013– |
| Amber Zibritosky | Stow Municipal Court | – |
| Kenneth G., Jr. Ziebarth | Superior Court of California, County of San Bernardino | 1975–1991 |
| Annette K. Ziegler | Wis. | 2007– |
| Donald Emil Ziegler | W.D. Pennsylvania | 1978–2003 |
| Todd Ziegler | Monroe County Circuit Court | – |
| William F. Ziegler | Superior Court of New Jersey, Cumberland/Gloucester/Salem Vicinage | – |
| Daniel F. Zielinski | Hendricks Circuit Court | – |
| Patrick John Zika | Superior Court of California, County of Alameda | 1998– |
| Thomas Samuel Zilly | W.D. Washington | 1988– |
| Gerald Lee Zimmerer | Tex. App. | 2019–2024 |
| Bernard Zimmerman | N.D. California | 1995– |
| Charles Ballard Zimmerman | Ohio | 1933–1969 |
| Joseph Zimmerman | Superior Court of California, County of Imperial | 1998–2010 |
| Michael D. Zimmerman | Utah | 1984–2000 |
| Colleen Zingaro | Connecticut Superior Court | – |
| Ed Zink | Thirteenth Judicial District Court | – |
| Steven L. Zinter | S.D. | 2002 |
| Allyson Zipp | Thurston County Superior Court | – |
| Jennifer Guerin Zipps | D. Arizona | 2011– |
| Alfonso Joseph Zirpoli | N.D. California | 1961–1995 |
| Danah L. Zirpoli | Texas 64th District Court | – |
| John Randolph Zitny | Superior Court of California, County of Orange | 2015– |
| Gregg W. Zive | Bankr. D. Nevada | 1995– |
| Thomas A. Zlaket | Ariz. | 1992–2002 |
| William J. Zloch | S.D. Florida | 1985– |
| Rya Weickert Zobel | D. Massachusetts | 1979–2026 |
| John F Zoll | New York City Criminal Court, Queens County | – |
| Allen Zollars | Ind. | 1883–1889 |
| John B Zollo | Suffolk County District Court | – |
| Layla Zon | Superior Court of Georgia, Alcovy Judicial Circuit | – |
| Jeremiah D. Zook | Court of Common Pleas of Franklin & Fulton Counties | – |
| Paul A. Zoss | D. New Jersey | 1997– |
| Jack Zouhary | N.D. Ohio | 2006– |
| Zachary O. Zoz | Fairfield Municipal Court | – |
| Joseph Stephen Zuccaro Jr. | Miss. | 1987–1989 |
| David S Zuckerman | New York Supreme Court, 9th Judicial District | – |
| Evan M Zuckerman | Suffolk County District Court | – |
| Leigh Zuerker | Twelfth Judicial Circuit Court | – |
| Thomas P Zugibe | New York Supreme Court, 9th Judicial District | – |
| Donald R. Zuidmulder | Brown County Circuit Court | – |
| Helen E. Zukin | Superior Court of California, County of Los Angeles | 2018– |
| David R. Zulfa | Superior Court of California, County of Kern | 2015– |
| Andrew L. Zumbar | Alliance Municipal Court | – |
| John Zunic | Superior Court of New Jersey, Essex Vicinage | – |
| Barbara Ann Zúñiga | Superior Court of California, County of Contra Costa | 1995–2014 |
| Vincent Zurzolo | Bankr. C.D. California | 1988– |
| Raymond F. Zvetina | Superior Court of California, County of San Diego | 1989–2002 |
| Cheryl R. Zwart | D. Nebraska | 2009– |