10 Vistra legal leaders
Stephanie Zapata Moore, EVP, General Counsel, and Chief Compliance Officer at Vistra Corp., is one of ten Vistra legal leaders listed here, alongside people who hold vice president and associate general counsel and assistant general counsel roles at the company. A reader can learn how legal leaders work at Vistra from people who have held the role.
Professionals to explore
Amy Simcox
LinkedInExperience: Vice President & Assistant General Counsel - Real Estate · Vistra Corp.
Amy Simcox has been Vice President & Assistant General Counsel - Real Estate at Vistra Corp. since March 2026, based in the Dallas-Fort Worth area. Amy Simcox also held the Vistra roles of Managing Counsel - Real Estate (2025 to 2026), Senior Counsel - Real Estate (2021 to 2025) and Counsel - Real Estate (2019 to 2021), and was an Associate Attorney at Greenberg Traurig, LLP from 2015 to 2019.
Casey Moore
LinkedInExperience: Assistant General Counsel - Litigation and Commercial Disputes · Vistra Corp.
Casey Moore has been Assistant General Counsel - Litigation and Commercial Disputes at Vistra Corp. since March 2026, based in Dallas. Casey Moore also held the Vistra roles of Managing Counsel - Litigation and Commercial Disputes (2023 to 2026) and Senior Counsel - Litigation and Commercial Disputes (2018 to 2023), and was a Shareholder at Greenberg Traurig, LLP and a Senior Associate at DLA Piper.
David Mitchell
LinkedInExperience: Assistant General Counsel, Environmental · Vistra Corp.
David Mitchell has been Assistant General Counsel, Environmental at Vistra Corp. since March 2026, based in Dallas. David Mitchell also held the Vistra roles of Managing Counsel, Environmental (2024 to 2026) and Senior Counsel, Environmental (2018 to 2024), and was a Partner at Balch & Bingham LLP from 2017 to 2018 and an Associate at Balch & Bingham LLP from 2009 to 2016.
Jessica Brown
LinkedInExperience: Director of Legal Operations · Vistra Corp.
Jessica Brown has been Director of Legal Operations at Vistra Corp. since February 2026, based in the Dallas-Fort Worth area. Jessica Brown also held the roles of Legal Project Manager at Barnes & Thornburg LLP (2024 to 2026), Business Development Technology Manager at Haynes and Boone, LLP (2023 to 2024) and Director of Marketing and Business Development at Thompson, Coe, Cousins & Irons L.L.P. (2020 to 2023).
Jessica Harris Miller
LinkedInExperience: Vice President Regulatory Compliance · Vistra Corp.
Jessica Harris Miller has been Vice President Regulatory Compliance at Vistra Corp. since March 2023, based in Austin, Texas, with the profile headline VP & Associate General Counsel, Regulatory Compliance at Vistra Corp. Jessica Harris Miller also held the role of Regulatory and Compliance Managing Counsel at Vistra (2018 to 2023), was an Attorney at Bracewell LLP and clerked on the U.S. Court of Appeals for the Fifth Circuit.
Martine Trinka
LinkedInExperience: Senior Counsel & Senior Director Regulatory Reporting · Vistra Corp.
Martine Trinka has been Senior Counsel & Senior Director Regulatory Reporting at Vistra Corp. since December 2025, based in Dallas. Martine Trinka also held the Vistra roles of Senior Counsel, Retail Operations (2024 to 2025) and Counsel, Retail Operations (2019 to 2024), and the Crius Energy, LLC roles of Vice President, Senior Counsel Corporate, Regulatory & Compliance (2018 to 2019) and Counsel (2012 to 2018).
Meagan Horn
LinkedInExperience: Senior Vice President, General Tax Counsel · Vistra Corp.
Meagan Horn has been Senior Vice President, General Tax Counsel at Vistra Corp. since March 2026, based in Dallas, with the profile headline Head of Tax at Vistra Corp. Meagan Horn also held the Vistra roles of Vice President, General Tax Counsel (2024 to 2026), Deputy Chief Tax Counsel (2024), Vice President of Investor Relations (2021 to 2024) and Associate General Tax Counsel (2020 to 2021).
Stephanie Zapata Moore
LinkedInExperience: EVP, General Counsel, and Chief Compliance Officer · Vistra Corp.
Stephanie Zapata Moore has been EVP, General Counsel, and Chief Compliance Officer at Vistra Corp. since April 2020, based in Dallas, and the profile also lists EVP and General Counsel at Vistra from October 2016. Stephanie Zapata Moore also held the roles of EVP, General Counsel, Chief Compliance Officer, and Corporate Secretary at Vistra Energy (2019 to 2020) and General Counsel at Luminant (2005 to 2016).
Tiffany Silvey
LinkedInExperience: VP & Associate General Counsel · Vistra Corp.
Tiffany Silvey has been VP & Associate General Counsel at Vistra Corp. since March 2026, based in Flower Mound, Texas. The profile also lists Managing Counsel at Vistra Corp. and Sr. Counsel at Luminant, both from April 2006, and Tiffany Silvey was an Attorney at Calpine from 2001 to 2006.
Yuki Whitmire
LinkedInExperience: VP and Associate General Counsel - Corporate Secretary, Securities Law and Corporate Transactions · Vistra Corp.
Yuki Whitmire has been VP and Associate General Counsel - Corporate Secretary, Securities Law and Corporate Transactions at Vistra Corp. since April 2020, based in Dallas. Yuki Whitmire also held the roles of Associate General Counsel and Corporate Secretary at Arcosa Inc. (2018 to 2020), Senior Counsel - Corporate, Securities & IT at Dean Foods (2016 to 2018) and Corporate Counsel at Akin Gump Strauss Hauer & Feld LLP.
Choose the right perspective
Choose the person whose title is closest to the legal decision you face, and note when their role began so you know how current their experience is. Weigh scope too, because a leader with broad responsibility and a director focused on one area see different parts of the work.
Questions to take into the conversation
- 01What took most of your time in your current legal role, and what did you change first?
- 02How did you weigh regulatory and litigation risk against what the business needed to move quickly?
- 03What did you carry over from earlier roles that changed how you practice law at Vistra?
Reaching Vistra legal leaders
How can I contact one of these Vistra legal leaders?
Pick one of the 10 people on this page and choose "Book a paid call", or describe your project to find others. You offer a fee for a 15-minute call or a written answer, Instant Expert finds the person's work email and sends the invitation, and they decide whether to accept. The list covers 1 company: Vistra Corp., based on profile data retrieved on October 18, 2026. Being listed here doesn't mean someone has agreed to take calls.
How much does it cost to reach Vistra legal leaders?
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Can an AI agent ask one of these Vistra legal leaders a question?
Yes. An agent with a USDC wallet on Base can ask one question without an Instant Expert account. It names the person, for example by the LinkedIn URL on this page, and pays per ask over x402 (HTTP 402). The person answers in writing or by voice note, and if nobody answers within 7 days, the payment goes back to the wallet automatically. Claude and ChatGPT can do the same through the Instant Expert connector: setup is at /docs/mcp for Claude and /docs/chatgpt for ChatGPT. x402 docs
About this directory
This is a professional research starting point based on business profile data retrieved on . Titles and companies reflect that source snapshot; roles marked former had ended by then. Check the linked profiles for current details. Inclusion does not imply Instant Expert membership or availability.
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