Middleton received a bachelor's degree from the University of Missouri in 1968 and graduated from the University of Missouri School of Law in 1971, becoming the third black graduate of the school.[3] After working for various offices within the federal government, including the EEOC, he returned to the University of Missouri in 1985. Since 1998, he was a deputy chancellor.[2] He retired as a deputy chancellor on August 31, 2015.[3]
He was appointed as interim president of Lincoln University in May 2017, serving until May 31, 2018.[4]