Clarissa Howley Mills, an environmental regulatory partner, has joined Holland & Knight in Dallas from Haynes Boone. She will focus her practice on environmental regulatory counseling, enforcement defense, permitting, litigation, due diligence and transactional matters, according to a news release.
Before joining Holland & Knight, Mills was a partner at Haynes Boone for one year. She previously spent nearly a decade with the U.S. Environmental Protection Agency, including serving as deputy regional counsel for EPA Region 6, where she managed one of the agency’s largest regional attorney offices and advised on permitting, remediation, state oversight and enforcement matters across a five-state region.
“Clarissa’s background including senior leadership roles at the EPA allow her to provide a practical understanding of both regulatory requirements and agency decision-making,” said Nicole Elliott, co-leader of Holland & Knight’s regulatory practice group. “Her experience aligns seamlessly with the Firm’s vision for growth in Texas as we continue to support and meet increasing demand for federal and state environmental counseling and enforcement capabilities, including work related to environmental due diligence, compliance, enforcement matters and related litigation.”
Mills’ arrival continues Holland & Knight’s lateral hires the firm has made in Dallas and across the state this year. The firm has expanded several key practice areas, including the recent move of state and local tax partners Sam Megally and Will LeDoux and senior counsel Cindy Ohlenforst in Dallas from K&L Gates.
Based on Lawbook 50 data, Holland & Knight recorded $337.6 in Texas revenue last year and ranks seventh among the largest firms in the state by headcount, with 291 lawyers in 2025.
AREAS OF FOCUS
Mills advises clients on environmental permitting, agency investigations, enforcement actions, compliance counseling, environmental due diligence and regulatory litigation. Her practice includes matters involving the Clean Air Act, Clean Water Act, Resource Conservation and Recovery Act, chemical accident prevention regulations and hazardous waste and toxic chemical programs. She also counsels clients on environmental considerations tied to corporate transactions and operational risk management.
EDUCATION
University of Kansas School of Law (JD, 2013)
Kansas State University (BA, 2010)