Garnett's research focuses on property, land use, urban development, local government law, and education policy.
In her inaugural research contribution for the Manhattan Institute, Garnett explores the legality of religious charter schools in light of Espinoza v. Montana Department of Revenue, in which the U.S. Supreme Court held that states cannot exclude religious schools from private school choice programs. Her report — "Religious Charter Schools: Legally Permissible? Constitutionally Required?" — explains why current laws prohibiting religious charter schools likely violate the First Amendment's Free Exercise Clause. Garnett goes further by outlining potential legislative, executive, and litigative paths to permit religious charter schools.
Garnett also contributed an essay, "Why We Still Need Catholic Schools," to the summer 2020 issue of City Journal, the quarterly magazine published by the institute.
"The Manhattan Institute is thrilled to welcome Garnett to our team," said Ray Domanico, the institute's director of education policy. "We are committed to expanding educational opportunities for all communities through a dedication to educational pluralism. Garnett's research and publications have contributed greatly to our understanding of the important public benefits that Catholic schools provide. She also has a record of explicating the legal standing and protection of religious and other schools of choice in our overall educational system."
At Notre Dame, in addition to her role as a Law School faculty member, Garnett is a fellow of the Institute for Educational Initiatives and the senior policy advisor for the Alliance for Catholic Education. She is the co-author of Lost Classroom, Lost Community: Catholic Schools' Importance in Urban America (University of Chicago Press, 2014), which she wrote with Professor Emerita Margaret Brinig, and the author of Ordering the City: Land Use, Policing and the Restoration of Urban America (Yale University Press, 2009).