About Erin Mersino

Erin Mersino has won and litigated many cases in our nation’s highest courts, including before the United States Supreme Court and most of the federal circuit courts of appeal, including the Second, Fourth, Fifth, Sixth, Seventh, Eighth, Ninth, Tenth, Eleventh, and D.C. Circuits.

She has worked on some of the most influential legal issues in our day, including the constitutionality of the Affordable Care Act under the Commerce Clause, the legality of the HHS Mandate under the Religious Freedom Restoration Act, and the scope of the First Amendment’s Free Exercise clause. Erin obtained the second injunction in the nation against the Obama Administration’s HHS Mandate.

Some highlights of her career include convincing Judge Easterbrook of the Seventh Circuit during oral argument to decide in her favor when he was disposed not to and arguing before seventeen judges of the Sixth Circuit sitting en banc. Recently, Erin won a several-weeks-long trial in U.S. District Court for the Western District of Texas in Austin. She has represented many high-profile Catholics and Christians, notably winning multimillion dollar cases for clients Tom Monaghan and Bill Donohue of the Catholic League.

Erin began her legal career as a criminal prosecutor. During her time prosecuting, she won one of the first domestic violence trials without the presence of a victim. When the victim was too afraid to appear for court, Erin was able to use evidence and testimony without violating the Confrontation Clause.

Erin graduated from the University of Michigan in Ann Arbor in three years and earned her juris doctorate from the Ave Maria School of Law, where she served on the Moot Court Board and received numerous honors, including Best Oral Advocate in Mock Trial.
In 2013, she received a Defender of the Faith Award from Legatus, a national organization for Catholic executives, and in 2025, she received the Distinguished Alumni Award from her law school.
Erin has appeared on national television programs, including Fox and Friends, On the Record with Greta Van Susteren, and a Kelly File Special: Who Is Teaching Our Kids? She enjoys writing, and her work has been published in USA Today, Politico Magazine, National Right to Life News, Live Action News, Life News, and American Thinker. Erin has been frequently interviewed on the radio and for news outlets including the Blaze, NPR, The Washington Times, The New York Times, The Laura Ingraham Show, Catholic Answers, The Drew Mariani Show, Catholic Connection with Teresa Tomeo, and LifeSite News.

Erin currently serves on the board of directors for several nonprofit organizations and previously served on the Council of the Religious Liberty Section of the State Bar of Michigan, where she held the offices of chairperson, secretary, and treasurer.

Her favorite part of being an attorney is having the opportunity to serve others, lift her clients’ spirits in times of tribulation, and enjoy the gift of hard work. She has a wonderful husband and five incredible sons, ages seventeen to six. Erin’s youngest son has the exceptionality of Down syndrome, which inspired her family to create a nonprofit that provides grants to schools that enable them to serve children of all types of abilities.

Erin is admitted to practice before the United States Supreme Court; the United States Court of Appeals for the Second, Fourth, Fifth, Sixth, Seventh, Eighth, Ninth, Tenth, Eleventh, and District of Columbia Circuits; the United States District Court for the District of Columbia; the United States District Court for the Western District of Texas; the United States District Court for the Eastern District of Michigan; and the United States District Court for the Western District of Michigan. She is also admitted to the Michigan State Bar and has appeared in several additional jurisdictions pro hac vice.