McLean served as NRL's superintendent for Information Technology Division since 2002. He was responsible for providing executive direction and technical leadership for the six division branches, supervising over 300 government scientists and contract support personnel, and formulating, selling, and executing the division’s program in basic research, exploratory development, and advanced technology demonstrations.
As superintendent McLean developed the scientific vision for future program direction for all Navy IT areas — including artificial intelligence (AI), autonomous systems, computer security, high assurance software, network technology, modeling and simulation, virtual reality, and high performance computing.
McLean began his federal career at NRL in 1980 shortly after completing dual degrees — a master’s in computer science and a doctorate in philosophy (Associate in Occupational Studies: mathematical logic) — from the University of North Carolina at Chapel Hill.
He started as a research computer scientist and principal investigator for several basic research projects. His work comprised formal techniques to develop, analyze, and apply security models; abstract, formal software specification languages; and proof technology for verifying specification and program properties.
Mclean helped form NRL’s Center for High Assurance Computer Systems between 1988 to 1994. He established and led its Formal Methods Section, responsible for research and consultation in formal methods for high assurance systems. He became the center's director in 1994 and then the Senior Scientist for Information Assurance in 2000 to 2002. He supervised the center’s 50 scientists and support personnel; formulating, selling and executing its research program in the areas of communication security, computer security, formal methods, network security, INFOSEC certification and engineering, and software engineering.
McLean is an internationally respected researcher for computer security with work published in over 100 technical publications. He served as an associate editor for Distributed Computing, Journal of Computer Security, ACM Transactions on Information and System Security, and other international scientific journals.
McLean was also the U.S. Voting Member of the NATO Research and Technology Organisation (RTO) Information Systems Technology (IST) Panel; the U.S. Representative to the Technical Cooperation Program (TTCP) C3I Group; a Senior Research Fellow of the University of Cambridge's Centre for Communications Systems Research; and a member of the Scientific Advisory Committee of Cambridge's Isaac Newton Institute Program in Computer Security, Cryptology, and Coding Theory.
He was a conference and program chair for the IEEE Symposium on Research in Security and Privacy; the IEEE Computer Security Foundations Workshop, and COMPASS.
McLean also held positions as an Adjunct Professor of Computer Science at NSA’s National Cryptologic School and L'Université de Neuchâtel’s Troisieme Cycle Romand d'Informatique. He is recipient of the 2008 Presidential Rank Award of Meritorious Executive, the IEEE Computer Society Outstanding Paper Award, Distinguished Contribution Allowance from NRL, and three Alan Berman Research Publication Awards also from NRL.