She was nominated by Chief Justice Kim Myeong-su on March 6, 2023, and officially appointed to the court by President Yoon Suk Yeol on April 17, 2023.
After graduating from the Seoul National University College of Law and 25th class of the Judicial Research and Training Institute, she began her career as a judge for the Bucheon Branch of the Incheon District Court [ko] in 1996.
[1] In reflecting on her childhood, Jung described her parents as poor but hardworking and recalled how her mother, who was a devout Buddhist, would tell her to "become a Buddha who saves all people.
[5][6] Upon graduation from the Judicial Research and Training Institute, Jung was hired as a judge for the Bucheon Branch of the Incheon District Court [ko].
[2] In 2022, Jung presided over an appeal trial involving the sexual assault and murder of a 20-month old infant that received significant public attention.
On June 15, 2021, Yang Jeong-sik was accused of abusing his 20-month old stepdaughter by sexually assaulting her, beating her, twisting her arm, and throwing her against a wall.
[10] After conducting an appeal trial, a panel of the Daejeon High Court led by Jung increased Yang's sentence to life in prison.
[17] In declining to criticize the proposal, Jung stated "the Supreme Court ruling declared the debtor's responsibility, and I think that the actual process of receiving the money and realizing the payment could be separate areas.
[19] When questioned about the property at the hearing, Jung stated "there was no intention of gaining illicit profits" and claimed the farm was purchased by her parents under her name.
"[30] On September 26, 2023, Jung was part of a 7–2 majority on the Constitutional Court that found a criminal ban on citizen-run leaflet campaigns in North Korea was an unconstitutional restriction on free speech and violated the prohibition of excessive punishments.
[35] On June 2, 2024, the Constitutional Court dismissed two petitions that argued the government's relief measures in response to the sinking of MV Sewol in 2014 were inadequate and a violation of their fundamental rights.
[36] While the court had the authority to hear the case if there was an "exceptional interest in requesting trial" which included the protection of constitutional order or when there was a risk of infringement recurring, the court determined the issues had already been addressed in prior litigation and that "it is difficult to recognize the exceptional interest in requesting trial in this case due to the need for constitutional explanation.
"[36] Jung joined Justices Kim Kiyoung, Moon Hyungbae, and Lee Mison in dissenting, arguing "in a situation where the people's right to life is threatened by a large-scale maritime accident similar to a disaster such as the Sewol ferry disaster, the issue of the state's fulfillment of its duty to protect basic rights is likely to recur.
[36] On August 29, 2024, Jung joined a unanimous majority of the Constitutional Court in ruling the Carbon Neutrality Framework Act's failure to set a greenhouse gas emissions reduction target after 2031 was unconstitutional because it failed to protect basic rights.
[37] In 1997, Jung married Kim Byeong-sik, a fellow trainee at the Judicial Research and Training Institute who was later hired as a judge for the Seoul District Court in 1999.