McLean got a BA from Wellesley, where she studied French Literature and European History, as well as a degree from the University of Massachusetts in Microbiology. The biology degree she used immediately to work at the Sloan-Kettering Cancer Institute; her European interests would come into play after she received her law degree from Fordham University. She later studied at the Institute of European Studies at the Free University at Brussels, where she earned her degree in European Law, but before that she had worked as a patent attorney at Darby and Darby, where she focused on trademark law.
Fittingly enough, she taught courses on trademarks and European Law, also teaching a seminar on Intellectual Property Law at the Jagiellonian University in Cracow Poland. Her interests continue to be in intellectual property law and European law.