Justice Michael J. O'Neill

The Honorable Michael “Mike” Jerome O’Neill, age 87, passed away peacefully on September 22, 2026, in Dallas, Texas. Mike was a respected jurist who served his community for more than 30 years. He served on the Dallas County Court at Law No. 1, the 193rd District Court, and the Fifth District Court of Appeals. After his official retirement, Mike continued working as a Senior Judge until a year before his passing. He was an active member of St. Patrick’s Catholic Church for decades and served as a Eucharistic Minister.

Mike was born in Tyler, Texas, on March 7, 1939, and his family moved to Dallas in 1950. He graduated from Jesuit High School in 1957 and, ten years later, married the love of his life, Betty Jean "Jeannee" Bates. They were married for 59 years and had two children and two grandchildren. Mike was dedicated to and cherished by his many friends and family, who knew him for his witty humor, his generosity, and his favorite catchphrase, "whatever is right," said with both sincerity and sarcasm. He was predeceased by his brother, Shane O'Neill, and is survived by his wife Jeannee; sister Sharon O'Neill; son Sean O'Neill and his wife Catherine; daughter Shannon O'Neill and her husband Jamie Gibbs; and grandchildren Quinn and Corbin.

Mike was a lifelong learner, a true Renaissance man. Before his career in law, he was a mathematician: he earned a B.S. in Mathematics from MIT (1961) and a Ph.D. from the University of Kansas (1969), conducted research at the Institute for Advanced Study at Princeton, and taught at Northwestern, Notre Dame, and Indiana University South Bend. During that time, he began law school, earning his J.D. from Notre Dame in 1976 before moving home to Dallas. His curiosity never faded. While serving as a district judge, he took cooking classes at Dallas County Community College and prepared exceptional meals for family and friends. Later in life, he could often be found working through thick microbiology textbooks or his latest MasterClass course.

A Catholic Mass will be held on October 16, 2026, at 10:30 a.m. at St. Patrick’s Catholic Church, 9643 Ferndale Rd, Dallas, TX 75238. Additionally, please join us for a Celebration of Life gathering at the Sokol Athletic Center that same day anytime from 5:00 p.m. to 9:00 p.m., 7448 Greenville Ave, Dallas, TX 75231.

In lieu of flowers, the family asks that donations be made in Mike's memory to the Dallas Volunteer Attorney Program (https://dallasvolunteerattorneyprogram.org/donate/)

or the Golden Retriever Rescue of North Texas (https://www.goldenretrievers.org/donate/).