A leading physicist with a distinguished career in teaching, research, and managing complex organizations, Witherell has received numerous honors and recognitions for his scientific contributions and achievements, including the W. K. H. Panofsky Prize in Experimental Particle Physics from the American Physical Society in 1990.
He is a member of the National Academy of Sciences and is a fellow of the American Physical Society, the American Association for the Advancement of Science, and the American Academy of Arts and Sciences. This is the second national laboratory he has led; he headed Fermi National Accelerator Laboratory (Fermilab) from 1999 to 2005. He received his Ph.D. from the University of Wisconsin, Madison, in 1973 and his B.S. from the University of Michigan, Ann Arbor, in 1968.