Bloomberg Law
Feb. 25, 2021, 10:46 AM

They’ve Got Next: Environmental Law Fresh Face Martha Thomsen

Ellen M. Gilmer
Ellen M. Gilmer

Baker Botts LLP lawyer Martha Thomsen had just started a multi-phase environmental trial in Houston when the Covid-19 pandemic started sweeping across the U.S.

“Between the first portion of the trial and the second portion, the world just completely changed,” Thomsen said, recalling her flight back to Washington, D.C., on a nearly empty plane.

As a senior associate, Thomsen was working with a team of Baker Botts lawyers representing Exxon Mobil Corp. in a long-running legal conflict over whether the U.S. government should cover some of the costs of environmental damage at refineries in Texas and Louisiana.

The U.S. District Court for the Southern District of Texas pushed on with in-person proceedings for the bench trial’s second phase, beginning in mid-March 2020, but moved to a remote format for the final portion in April.

“Everyone was able to adapt pretty seamlessly from a live, in-person, full trial down physically in the Texas courthouse to a remote trial where there were still witnesses that had to be examined and ultimately closing arguments that had to be done,” Thomsen said, though she added that the experience was “surreal.”

The court ultimately ordered the government to pay Exxon more than $20 million. The U.S. is pursuing an appeal.

The case is just one example of the complex litigation issues Thomsen has gravitated toward since working as a summer associate at Baker Botts in 2011. It was during that summer that she developed an interest in environmental matters.

“I spent my third year in law school effectively playing catch-up because I didn’t at that time have much of an environmental law background,” she said. “I took every class that had ‘environmental’ in the name or ‘administrative law’ in the name.”

When she joined the firm as a full-time associate in 2012, she asked to join the firm’s environmental team.

“I remember struggling with the decision at the time because there were a lot of things I liked about general litigation, too,” she said. “But looking back, it was just one of the best decisions I’ve ever made. The same things that drew me to the group originally are the same reasons I’m still here.”

Thomsen said she loves the complexity and importance of environmental law and the opportunity to do both litigation and regulatory work for her clients. Her portfolio can be summed up as “all things waste and water,” she said, including Superfund, Resource Conservation and Recovery Act, Toxic Substances Control Act, and Clean Water Act issues.

Scott Janoe, chair of the environmental, safety, and incident response section at Baker Botts, said Thomsen is a “natural” at the job.

“Martha is on a path to becoming the preeminent environmental litigator of her generation,” he said. “She shows tremendous practical and strategic thinking skills across all kinds of environmental disputes.”

Thomsen’s work involves numerous fast-moving regulatory issues that keep her on her toes, including coal ash and emerging contaminants known as “forever chemicals"—two areas that are poised for more changes under the Biden administration. Her work on waste issues has also expanded into the renewable energy space.

“One thing that’s been great about this practice is that it continues to evolve,” she said. “So there are some of the traditional waste management issues that I’ve dealt with my entire time at the firm, but as our clients’ industries evolve, so do we.”

To contact the reporter on this story: Ellen M. Gilmer in Washington at

To contact the editors responsible for this story: Lisa Helem at; Rebecca Baker at