Renner is Of Counsel in Hausfeld’s New York office. He is a dynamic litigator, whose practice focuses on pursuing justice for plaintiffs in a wide range of complex cases involving natural resources, environmental justice, civil and human rights, toxic torts, antitrust, consumer protection, and cybersecurity. He also maintains a strong public entity practice, representing state governments and one of the largest water authorities in the United States in environmental litigation.

Recently, Renner served as a key part of Hausfeld’s team in In re: T-Mobile Customer Data Security Breach Litigation. The team secured a $500 million settlement for a class of more than 76 million victims of T-Mobile’s 2021 data breach.

Before joining Hausfeld, Renner worked at a prominent national plaintiffs’ civil litigation firm, where he represented thousands of children who were lead poisoned in the Flint Water Crisis. He was the firm’s primary appellate and complex motion attorney, briefing and arguing a wide array of dispositive, jurisdictional, evidentiary, and Daubert motions in both trial and appellate courts across the country.

Previously, he served as an Assistant Attorney General in the Iowa Attorney General’s Office, where he practiced environmental, administrative, and constitutional law. He advised administrative agencies and litigated cases involving novel issues of constitutional, statutory, and regulatory law, all while maintaining a busy administrative prosecution docket. He began his legal career by serving as the judicial law clerk to the Honorable Mark S. Cady, Chief Justice of the Iowa Supreme Court.

Renner earned his J.D. with highest honors in 2012 from Drake University Law School, where he was elected to the Order of the Coif and the Order of the Barristers, served on the Editorial Board of the Drake Law Review, and captained Drake’s environmental law moot court team. In 2017, he held a graduate research fellowship in environmental law at the Elisabeth Haub School of Law at Pace University, where he also earned an LL.M. in Environmental Law, summa cum laude.

In 2023, Renner was recognized in the Bold Award category, an award given to those persons who have demonstrated a fearless approach to litigation or problem solving, one of five award categories that make up the Hausfeld Values Awards, an annual recognition program that highlights the achievements of Hausfeld team members based on their significant contributions made and results achieved over the prior calendar year. His tireless work on behalf of plaintiffs was recognized in 2024, when he was named a Rising Star of the Plaintiff’s Bar by the National Law Journal.


Renner has represented clients in federal, state, and administrative courts across the country. He represents individuals, governments, and businesses seeking justice. Some of his current and former clients include one of the largest water authorities in the country against chemical companies who manufactured 1,4-dioxane, farmers who were sold defective crop treatments, whistleblowers who warn of dangerous products and fraudulent practices, children who were poisoned by lead in drinking water, workers harmed by defective products, and state administrative agencies responsible for protecting the environment and public health.