Dr. Vernon, who was known as "Mac," proved that intelligence is distributed as equitably among deaf people as it is among the hearing population. During his two decades at Western Maryland College in Westminster — later renamed McDaniel College — Dr. Vernon was the driving force that made that institution a leader nationally in deaf education.
Dr. Vernon died Wednesday at his home in St. Augustine, Fla.The specific cause of his death has not been determined. He was 84.
Dr. Vernon's widow, Marie Vernon, said that her husband's breakthrough research began in the 1960s when he was working at Chicago's Michael Reese Hospital. Dr. Vernon surveyed over 50 years of research on intelligence testing, and what he found upended what was then conventional wisdom: that a hearing deficit imposed limitations on intelligence.
"He showed that the IQ tests for hearing children didn't adequately assess the intelligence of deaf children," Mrs. Vernon said. "He determined that to get a true picture, you had to test deaf children's nonverbal intelligence. What he did was really seminal, because at the time there was the lingering assumption that to be deaf was to be dumb."
Dr. Vernon was born in Washington D.C., and moved to Florida at age 13 after his father died. He served as a private in the Army in Korea from 1946 to 1948 in military intelligence. Upon his discharge, he enrolled in the University of Florida, where he earned a bachelor's degree in psychology in 1951.
His wife said that a job keeping inventory for a school for the deaf in Florida, where he became proficient in sign language, inspired him to apply for and win a scholarship to Gallaudet University in Washington. While he was a graduate student, he fell in love with and later married a deaf classmate, Edith Goldston.
"He became totally committed to deafness when he married Edith," Mrs. Vernon said. "It was through her that he got a much deeper understanding of what it meant to be a deaf person in a hearing world."
Dr. Vernon earned a master's degree from Gallaudet in 1955. He later earned a second master's degree from Florida State University and a doctorate from California's Claremont Graduate University in 1966.
He began teaching at Western Maryland College in 1969 and didn't fully retire from teaching until 1991. When he was hired, the college had no provisions for American Sign Language, no interpreters, no deaf education curriculum and just one deaf student. Dr. Vernon changed all that.
One of his early students was Jean Andrews, now a professor of deaf studies at Lamar University in Texas.
"Personally and professionally, Mac was my hero," Dr. Andrews said.
"Western Maryland was considered very innovative because it accepted deaf students into its graduate education program. At that time, deaf people weren't even being admitted into graduate school at Gallaudet," she said. "Mac was a real pioneer. He talked about how deaf people should be running their own schools. I came in off the civil rights movement of the 1960s, and Mac was one of the first people to talk about civil rights for the deaf."
Dr. Vernon co-wrote six books and was involved in the production of 20 documentary films. One book, "They Grow in Silence," which Dr. Vernon wrote with Eugene D. Mindel, later served as the basis for the documentary of the same title, which won the Public Broadcasting Award for Public Service in 1972.
In addition, Dr. Vernon was the editor of American Annals of the Deaf for two decades.
He won many awards during his long career. Chief among them was the 2007 Gold Medal Award for Life Achievement by the American Psychological Association. He also received the Medal of Honor from the British Association of the Deaf, the Declaration of Merit from the World Federation of the Deaf and the American Psychiatric Association Award for career contributions to mental health and deafness.
Dr. Vernon's first wife, Edith, died in 1988.
A celebration of Vernon's life will be held Sept. 22 in St. Augustine.
He is survived by his second wife; a daughter, Eve Vernon Peters of Riverton, N.J.; a brother, Col. (ret.) Graham Vernon of Carlisle, Pa.; a sister, Therese Douglass of Tallahassee, Fla.; and six stepchildren.