Eileen Penner briefs and argues complex appeals in a wide range of commercial and constitutional cases. She also advises clients regarding civil rights and affirmative action issues. She has presented arguments in the US Supreme Court, First, Second, Third, Seventh, Eighth, and Eleventh Circuits, the Supreme Courts of Delaware, Nebraska, and New Hampshire, and multiple state courts of appeals. The National Law Journal noted her remarkable record of success in cases she briefs and argues, including her in its “Forty Under 40” list of America’s most successful litigators. Prior to joining Mayer Brown, she worked in the Civil Rights Division at the US Department of Justice, first as a trial lawyer and later handling appeals.