Mimi S. Dennis

Overview

Mimi S. Dennis represents leading national and global companies in commercial, civil, and product liability litigation and product regulatory counseling matters. Her clients include Class I and short line railroads, manufacturers, distributors, importers, and retailers.

With a focus on the rail, automotive, pharmaceutical, energy, and construction industries, Mimi defends clients in multidistrict proceedings, arbitrations, and other complex litigation. She also has first chair bench and jury trial experience. Mimi understands the nuances of the industries in which her clients operate, and she strives to help them balance litigation risks with business goals. Clients appreciate her hands-on approach and her sincere interest in developing strong personal relationships and a deep understanding of their businesses. Staying current on litigation issues, Mimi has published several articles on environmental and civil litigation matters, ranging from a discussion of class action certification to defenses in pharmaceutical failure-to-warn cases.

On the counseling side of her practice, Mimi helps clients limit risk and avoid liability and compliance issues. Representing clients in the food, beverage, chemical, medical device, and pharmaceutical industries, she handles regulatory matters before federal and state agencies, including FDA, EPA, and IRBs. Acting as an advisor to her clients, she carefully assesses risks, recommends actions, and counsels clients on contract formation, negotiation, and interpretation.

Mimi is a member of the firm’s Mass Tort, Product, and Consumer Litigation; Product Risk Management; and Transportation groups. She has been a member of the Law360 Transportation Editorial Board since 2024, and was accepted as a member of the General Counsel Committee of the American Short Line and Regional Railroad Association (ASLRRA) in 2024. Mimi maintains an active pro bono practice focused on providing legal services to immigrant women and girls who are survivors of gender-based violence and has also served as a guardian ad litem in D.C. Superior Court.

Career & Education

Georgetown University Law Center, J.D., 2000
Georgetown University, B.S., cum laude, 1996
- Georgetown University Law Center, J.D., 2000
- Georgetown University, B.S., cum laude, 1996
District of Columbia
Maryland
U.S. District Court for the District of Columbia
U.S. District Court for the District of Maryland
U.S. Court of Appeals for the Third Circuit
U.S. Court of Appeals for the Seventh Circuit
Supreme Court of the United States
- District of Columbia
- Maryland
- U.S. District Court for the District of Columbia
- U.S. District Court for the District of Maryland
- U.S. Court of Appeals for the Third Circuit
- U.S. Court of Appeals for the Seventh Circuit
- Supreme Court of the United States
Member, Law360 Transportation Editorial Board, 2024–Present

Member, General Counsel Committee of American Short Line and Regional Railroad Association (ASLRRA), 2024–Present
- Member, Law360 Transportation Editorial Board, 2024–Present
- Member, General Counsel Committee of American Short Line and Regional Railroad Association (ASLRRA), 2024–Present

Mimi's Insights

Blog Post | 04.22.25

Rail Derailment Trial Update: GATX and OxyVinyls Say “Case Closed”

Blog Post | 04.17.25
Rail Derailment Trial Kicks Off: Who Pays For East Palestine?
Press Coverage | 03.19.25
Law360 Announces The Members Of Its 2025 Editorial Boards
Blog Post | 03.03.25
NHTSA Administrator Nominee

View All Insights

Representative Matters

Transportation and Railroad

Defended a Class I rail carrier in an insurance subrogation case in which the plaintiffs sought close to $20 million in damages. After the claims were significantly narrowed at summary judgment, the jury returned a verdict for the defendant following a week-long trial, rejecting all of the plaintiffs' claims.
Representing a Class I rail carrier in class action litigation in which the plaintiffs seek damages and medical monitoring for alleged chemical exposure following a derailment.
Representing a Class I rail carrier in multiple wrongful death proceedings, in which the plaintiffs seek more than $600 million in damages.
Representing a Class I rail carrier in proceedings brought by a municipality and business owners to recover for flood-related property-damage.
Key member of an independent third-party team overseeing a consent order between the National Highway Traffic Safety Administration (NHTSA) and a large American automobile manufacturer for failing to comply with federal recall requirements. On that team, oversees and makes recommendations on the manufacturer’s compliance with federal regulations and the Vehicle Safety Act.

Pharmaceutical

Defending a Fortune 20 health care services company in one of the largest multidistrict litigations in the nation, involving class action and personal injury claims of alleged pharmaceutical contamination and defects.
Defended a Fortune 20 health care services company in a series of wrongful death and serious personal injury cases arising out of claims of alleged contamination of over-the-counter medication.

Energy

Defended a major oil company in a multidistrict litigation involving claims brought by municipalities, water districts, and state sovereigns across the country.
Defended a major oil company in a consolidated gasoline oxygenate product liability litigation alleging injuries to water resources, including an action brought by the New Jersey Department of Environmental Protection seeking natural resource damages on a statewide basis for alleged impairment of groundwater resources.
Defended a major oil company in an arbitration regarding LNAPL contamination at a petroleum storage terminal. Plaintiff’s claims exceeded $15 million; received a defense verdict after a week-long binding arbitration.

Architecture and Construction

Defended an architectural firm in a three-week arbitration regarding claims of defective design associated with the construction of a private museum and residence, resulting in a de minimus award for the property owner.
Defended a joint venture engineering and construction company in a contract dispute associated with claims of defective fireproofing coating in a multi-billion-dollar liquid natural gas shipping terminal.
Defended a construction company and its CFO against claims of fraud, misrepresentation, and breach of fiduciary duty.