Dr. Dale Carrison, who works in 14 medical arenas, listens to University Medical Center patient Lilian Ancheita describe her symptoms last month. Carrison is the state's homeland security chairman, a tactical physician for the Metropolitan Police Department's SWAT unit and medical director for the Clark County Fire Department, Mercy Air and the Las Vegas Motor Speedway. Photo by Gary Thompson. Dr. Dale Carrison, chairman of Nevada's Homeland Security Commission, testifies before a legislative panel. Photo by Brad Horn/The Associated Press Dr. Dale Carrison talks recently with University Medical Center transportation worker Cecil Parson at the hospital. As a youth, Carrison got into trouble with the law and he flunked classes. After a career in law enforcement, he battled depression. And he didn't even think about going into medicine until his 40s. Photo by Gary Thompson.

As a deputy sheriff in Orange County, Calif., Dale Carrison was accustomed to kicking down doors and taking out wanted felons with a well-executed body slam.

"Nobody went after the bad guys like he did," said his one-time colleague, Roger Hoxmeier. "Nobody knocked down more doors. He had so much energy."

But Hoxmeier saw another side to Carrison, now the head of Nevada's Homeland Security Commission.

It was some 40 years ago when Carrison was accompanying Hoxmeier on a walk-through of his new house. In the yard, Carrison used his knowledge of 18th century texts to list the Latin names of Hoxmeier's plants.

"You never know where his mind is going to take him," said Hoxmeier, now retired and living in Reno.

His conclusion: "He is so passionate about life, about learning and trying to make the world a better place."

That hasn't always been the case.

Carrison, now 65, took a long and circuitous route to his current roles, not only as homeland security chairman but as a tactical physician for the Metropolitan Police Department's SWAT unit and medical director for the Clark County Fire Department, Mercy Air and the Las Vegas Motor Speedway.

As a youth, he got into trouble with the law and he flunked classes. After a career in law enforcement, he battled depression. And he didn't even think about going into medicine until his 40s.

Today he works in 14 medical arenas. He can be seen cautioning emergency workers before NASCAR races, imploring the Legislature for resources to treat the mentally ill, advising the governor on the state's homeland security needs, or simply calming a patient in the emergency room at University Medical Center.

"I'm just amazed at him," says Clark County Sheriff Bill Young, who frequently works with Carrison on security and SWAT issues. "He has an ability to compartmentalize and focus like no one I've ever seen."

He's got his critics, but even they acknowledge his ability.

"I would certainly trust him with me and mine," says Dr. James Tate, who is leery of Carrison's past, in part because of some of the investigations Carrison carried out as an agent with the FBI.

It was, Carrison said, a "monster midlife crisis" that propelled him into his current life.

These days, he worries that too many people, as the writer Henry David Thoreau observed, live lives of quiet desperation. And he believes too many young people give up on the future after they make mistakes.

"As long as you're alive and capable, you can find a way to go after what makes you most productive and most happy," said Carrison, who stands 6 feet 4 inches tall and has a thick shock of grey hair. "There is no reason to ever give up on life. I'm living proof you can screw up and still go forward."

Carrison was born to a farmer and housewife in the small farm town of Macomb, Ill. He spent his boyhood in Georgia, California and Florida.

With his parents' marriage in turmoil when he was a teenager, Carrison turned rebellious while living in Pensacola, Fla. He blacked out from alcohol for the first time at age 16. He and a friend used gunpowder to manufacture explosive devices.

"What they made was more powerful than firecrackers but they didn't blow up anything more than a garbage can," said Downing Gray, who was with Carrison when he and two other friends were arrested.

One time, Carrison recalled, "One of the members of our group took his dad's car and we went racing. The police caught us."

The teens were taken to jail and had to be bailed out by their parents.

"I was pretty screwed up as a kid," he said.

Hoping to save their son, his parents sent him to a military school for a summer. He also joined the Naval Reserves. The discipline helped. But his previous school grades were so poor that it didn't appear he could get into college. His standardized test scores, however, were good enough to get him into Florida State University in 1958.

"Unfortunately, I turned into a partier," Carrison said. "I began to have problems once again with alcohol."

Flunking out of school and about to get drafted into the Army, Carrison opted to enlist in the Navy.

It was while in boot camp that a transformation occurred. He fed off the discipline and having to prove himself to other young men.

"That was the first time I had success as a leader," he said. "I became the honor man."

Despite his scholastic record, Carrison asked naval authorities to let him test for the enlisted prep school for the Naval Academy. To their surprise, he passed, attended the prep school and ended up passing the test to get into the Naval Academy. He earned an enlisted appointment to the prestigious school.

His heart was set on becoming a Naval pilot. But a shoulder injury he suffered while wrestling ended that dream and he dropped out of the school. He joined his parents in California and started attending a junior college. While there, he met his first wife, whose father had been a reserve deputy in Orange County. "That's how I became interested in law enforcement," Carrison said.

He got a job as a deputy sheriff and earned his associates and bachelors degrees in police science.

"I finally realized that if I worked hard I could have real success," he said. "People want you to succeed, but they want to see you make the effort."

The work was dangerous, Hoxmeier, his colleague on the force, said.

"There was no SWAT team to help you get people out, no specialized equipment to use when you went in after somebody. You knocked down the door and then you and your partner had to bring the guy under control."

His ability to catch wanted fugitives didn't go unnoticed. The FBI recruited him and he moved to Portland, Ore., his first duty station. He broke bank robbery cases and was then transferred to Los Angeles. Carrison, who by then had obtained a pilot's license, flew surveillance flights for the bureau.

"He was a real charger," said retired FBI special agent Andrew Stefanak, who served on a squad with Carrison. At a party for FBI agents, Stefanak said, one agent who had been a former Army Airborne Ranger dared other agents to parachute out of a plane with him.

"Carrison and another agent took him up on it without having any training," Stefanak said. "The other agent started having second thoughts in case anyone got hurt. But fortunately no one did."

Training in riding motorcycles led Carrison to FBI undercover work. On one case, Carrison was dressed as a motorcyclist pretending to fix his bike while surveilling a suspect who had threatened to detonate a nuclear device. The suspect paid no heed to the would-be biker and picked up a package that "supposedly had extortion money in it," Carrison said. He placed the package in his station wagon and drove away. "At that time, he was bought and paid for," Carrison said. "After a short high-speed chase, we apprehended him,"

Carrison also did investigative work on the Black Panthers and other groups the FBI deemed radical, including the Symbionese Liberation Army, behind the 1974 kidnapping of newspaper heiress Patricia Hearst.

After five years as a special agent, though, Carrison became fed up with the bureaucracy. He found there were too many rules, and the glacial pace was frustrating.

So he went to work with his father, helping him run his auto parts store.

FBI agents were surprised, doubting that he'd find fulfillment.

Carrison had divorced and remarried by then. His second wife, Kathy, said the chance to be with his father, "who he hadn't been as close to as he would have liked growing up," had a lot to do with his decision.

His FBI colleagues were right. Carrison did feel the need to contribute to society more. He went after a graduate degree in biology while working at auto parts stores. He thought he might become a college science teacher. But a counselor at UCLA said aptitude tests showed he could be a doctor. She also said he shouldn't let his age -- he was 43 -- deter him. She knew of a 36-year-old, she said, who had just started medical school.

After conferring with Kathy, he decided to go for it.

"I couldn't have done it without her," Carrison said. "What an opportunity. To become a true agent for helping people."

Carrison said he soon found the application process for medical school dehumanizing. Several universities sent back letters stating that he wasn't rejected because of his age.

"The most prejudicial statement a person can make to another person is that we're not doing this because of race, ethnic background, age or whatever," Carrison said. "My question to them was, 'Then why did you even bring it up?'"

Finally, he got accepted by the College of Osteopathic Medicine of the Pacific in Pomona, Calif.

Loans, money from one of the auto parts stores, and Kathy's work helped the family stay afloat financially.

When Carrison was interning in Flint, Mich., members of the Carrison family lived in a one-bedroom apartment near the hospital.

"We didn't have money," said his daughter, Michelle DiMauro. "That time, with four of us in the one bedroom apartment, was a real challenge. Believe me, he doesn't have the God complex so many people say doctors have."

Following medical school graduation in 1987 and a residency in Illinois, Carrison held positions in Illinois and Wisconsin before coming to University Medical Center in 1991 as an emergency physician.

He threw himself into his work, happy to be in a growing community where doctors were prized. The more work he did, the more people wanted him. His ability to lead, which had been obvious in police situations, also served him well in medical situations. Soon he was promoted to management positions.

Shortly after arriving in Las Vegas, Carrison met Dr. Terry Lewis, a trauma surgeon who needed someone to help him provide medical support to the motor sports community. Carrison volunteered. That was before the Las Vegas Motor Speedway was built, but Carrison would make the key connections that would help him become the natural head of medical services at the new speedway.

"I don't think there's a better run medical service at any NASCAR track in the country," said NASCAR driver Jeff Burton before a 2005 race at the track.

Carrison's passion was never more evident than when he testified in 2004 before the Legislative Committee on Health Care regarding unnecessary emergency room use by the mentally ill, people who actually needed psychiatric care but who had no other place to go for help.

"I am fighting a war," he thundered. "This inappropriate use of the emergency room places the life of every man, woman and child in Southern Nevada at risk. Every day our hospital emergency departments have multiple patients waiting on ambulance stretchers in the hallways and our waiting rooms are filled to capacity ... they could die waiting."

His emotional plea for funding to treat the mentally ill, according to health officials, helped get the treatment funds that recently led to the Clark County Commission's lifting a health care declaration of emergency.

The reason Carrison can hold so many positions, according to nurse Jeri Dermanelian, assistant clinical manager for the UMC emergency department, can be partially attributed to his wife.

Often, Dermanelian said, Kathy Carrison takes care of the details that make meetings or parties work. "She's the one that makes sure that nurses are invited to things like he wants," she said. "To Dale, nurses are so important and are included in everything. That's why our emergency department works so well. Unlike so many doctors' wives, she has no problem relating to nurses. There is no wall up."

But Tate, the Las Vegas physician, is uneasy about Carrison's past as an FBI investigator.

"Dale and I don't always see eye to eye on things," Tate said. "Part of that is because of his background in the FBI. I didn't appreciate what the FBI did in investigating some groups. I got investigated. I would characterize it as difficult for him to get out of that mold."

Tate, who is black, said he also didn't think Carrison and others on a selection committee gave a black candidate he supported for head of the UMC Trauma Center a fair hearing a few years ago.

Carrison said the candidate got a fair hearing, but the selection panel found Dr. John Fildes a better candidate. Fildes, now head of the UMC Trauma Center, recently was appointed as the national chairman of the prestigious American College of Surgeons Committee on Trauma.

Carrison said he has no apologies for investigating groups such as the SLA or the Black Panthers.

"Any group, black, white or purple, that advocates violence against the United States government should expect to be investigated," he said.

Along with his work heading the Homeland Security Commission, Carrison these days can be found working on patients at the UMC Trauma Center and St. Rose Dominican Hospital.

UMC trauma surgeon Dr. Dave MacIntyre, who works with Carrison at the Las Vegas Motor Speedway, said he'll look up while working on a trauma case and see Carrison nodding and smiling.

"He looks like a proud father when we carry out what he wants," MacIntyre said.

Mike Benassi, who just graduated from the University of Nevada School of Medicine at 42, said he phoned Carrison after he heard that the doctor had started medical school late in life.

"I was a bartender and decided I wanted to do something more with my life," Benassi said. "I didn't know how to go about it and Carrison set aside an hour for me to talk with him. He didn't have to do that. It was incredible."

Carrison is particularly excited these days about a new emergency medicine residency program being developed through the University of Nevada School of Medicine and UMC. "I think it's very important for the kids going to school here to use their talents where they received their medical education," he said. "The emergency medicine residency will allow them to do that."

Recently, Carrison found himself trying to help Lilian Ancheita in the UMC emergency room. The anemic Spanish-speaking woman was suffering obvious abdominal pain. He held her arm in a show of concern. Though he speaks passable Spanish, he had an interpreter with him.

"There's something going on here and we have to find out what it is," he told the woman through the translator.

"Gracias," Ancheita said.

Why people respond so positively to Carrison, Dermanelian said, is simple: "He backs his people -- all of them in emergency services, including the patients. It doesn't matter whether they're doctors, nurses or in environmental services or whether they are rich or poor or what color they are. He's forever thanking people for what they do. He's not just one of those guys that stands back and directs people. He jumps in and does mouth-to-mouth or CPR or whatever is needed."

Ironically, Carrison has been on the receiving end of work by emergency medical professional many times.

The longtime motorcycle rider, who has enjoyed whipping around the Las Vegas Motor Speedway at well over 100 mph, Carrison has crashed on a couple of occasions, sustaining a broken wrist, a partially collapsed lung, broken ribs and a broken arm.

"He's really abused his body," Dermanelian said. "He came in once after a crash and told us what should be done."

Once while scuba diving in the 80s, he had a cerebral air embolus, essentially a bubble of air in the blood circulation in the brain, and he suffered what would be considered a stroke.

"Although it resolved, I had total paralysis on one side as a result of this," Carrison said. "I could not speak and I was blinded. Fortunately everything came back in a couple of days."

Carrison also has a condition that often sees his heart begin to beat far too fast.

On 24 different occasions he has gone through what is now a staple of TV medical dramas. A doctor yells "clear," and paddles are used to shock Carrison's heart back into rhythm.

On one occasion when the anesthetic wore off too quickly, Carrison felt the entire shock slam through him and he yelled so loudly inside the UMC Trauma Center that many said his screams probably could have been heard outside.

"Having been cardioverted with paddles or electroshock gives me a tremendous appreciation for what patients go through," Carrison said. "The injuries I've suffered also help me to relate to my patients. My scuba diving incident turned out to be a major impetus in my going into emergency medicine. I realized people needed better care than what I got. There were two decompression chambers within 26 miles of where my incident happened and I was sent to neither of these, even though I came into the emergency department wearing a wet suit and experiencing paralysis."

The paralysis also contributed to his once depressive state.

"In the darkest moments, I can recall contemplating suicide," he said.

But he said his mother was bipolar/manic depressive and it helped him understand that part of what he was feeling "was caused by some chemical imbalance and not all out of despair and feeling sorry for myself."

To have the opportunities open up for him as a physician, he said, was the turning point.

"This is like making up for lost time in my life, when I was wasn't as productive as I could have, or should have been."