Which still doesn't explain fully how he came to be Dr. Cop.
"Having grown up in a doctor's home," says Franklin County Sheriff Charles (Chuck) White, whom Mullen works for when he's not practicing neurosurgery in Dallas, "I naturally questioned why someone would give up the kind of salary a neurosurgeon makes to do the kind of work I do. But, the more I've gotten to know John, the better I understand. Law enforcement is a passion for him."
Mullen, enjoying a rare evening off, is returning from Dallas after attending a book-signing party for friend and mentor Roy Hazelwood, a famed FBI profiler. Before he reaches the turnoff that will take him to his lakeside home near Mount Vernon, Mullen's attention is drawn to a car that passes him at a high rate of speed. The off-duty deputy follows the car until it enters his Franklin County jurisdiction, then pulls it over.
Not only does the young driver receive citations for speeding and driving without a license but also gets a visit to the county jail, where he is asked to explain what he was doing with 10 pounds of marijuana in his car. A computer check later reveals that he was also wanted on an aggravated assault warrant that had earlier been issued in Dallas County. And that bust, Mullen says, is almost as satisfying as the one that resulted after he'd stopped to question a hitchhiker during a routine patrol of the 11 miles of Interstate 30 that runs through Franklin County. The man, it turned out, was wanted in Oregon for seven sexual assaults. Just another day on the job for the surgeon/officer, one that shows how big-city crime often follows Mullen to his country retreat.
Despite the joy he gets from such work, it didn't seem early on that his life would cross that thin blue line into law enforcement. In truth, as a young man, Mullen considered a variety of vocations. There was, of course, the medical profession, which his parents and several teachers back at Ticonderoga (N.Y.) High encouraged him to pursue; a possible career in the military; or maybe an application to the FBI Academy. Ultimately, he would opt to become a doctor, but only after a series of unexpected events.
It was while participating in ROTC drills during his third year as an undergraduate that he suffered a knee injury so severe that it made it necessary for him to drop out of school for a year. During his academic sabbatical, he began working as an assistant chemist in the state medical examiner's office in Burlington, Virginia. In time, Mullen estimates, he assisted in at least 1,000 autopsies--and developed a fascination for the forensic science.
"After I graduated [in 1970]," he recalls, "I went to work full time in the M.E.'s office. I did that for three years before my boss finally talked me into going to medical school. He told me about a new program at Southern Illinois University where you were offered a board exam which, if passed, amounted to completion of the first couple of years of med school. The bottom line was that if you could pass the exam and were accepted, you could be in and out of medical school in only two years."
Mullen drove all night from Burlington to Springfield, Illinois, stopped for a quick shower at a truck stop, reported for the exam, and was one of four candidates selected. By 1975, he was beginning his internship at Duke University Medical Center. In 1981, Mullen made the move to Dallas.
First as an instructor at the University of Texas Health Sciences Center of Dallas Southwestern Medical School, then as co-director of Parkland Hospital's Epilepsy Center, and finally in private neurological surgery practice, he enjoyed a steadily growing reputation and all the financial trappings his profession made possible. He worked long hours to afford such lifestyle amenities as his own plane.
In time, however, came what he describes as "the burnout." "Cutting on nerve tissue is extremely stressful," he admits. "It was exacting and demanding, the kind of thing that appealed to the perfectionist in me. But, unfortunately, there was also a lot of routine work. Frankly, I became more than a little weary of treating people with back pains. Hearing the constant complaints of patients became monotonous." His bedside manner, he admits, was deteriorating swiftly.
"I'm not sure," he adds, "that I fully realized it at the time, but working around the clock, doing the same thing over and over, had begun to wear on me." In truth, he says, the fame and fortune of the medical profession had never been the driving force in his career choice. It was the challenge that motivated him. And he had begun to feel that motivation slipping away.