He wakes up in the middle of the night at this time of year — bothered, sleepless. Tom Didone has gone to dozens of traffic fatalities that involve teenagers, arriving at scenes of shattering wreckage and telltale skid lines.

He is always struck by the senselessness of what he sees.

One night, the Montgomery County police captain arrived at a scene where his son was in an ambulance. Ryan Didone had been in the back seat of a Volvo station wagon headed to a Burger King. The driver had taken a winding road in Damascus at high speed, veered off and hit a tree.

Ryan was 15.

Didone knows that his son was not unlike other teens who might, in this season of proms and graduation parties, unthinkingly put themselves at risk. Maybe the driver is intoxicated. Maybe the issue is not alcohol at all, as in Ryan’s case, but something else: inexperience behind the wheel, speed, night conditions, distraction, multiple passengers.

“It only takes a second to take a life,” Didone told several hundred high school students in Burtonsville one day this month, hours before their prom.

Didone talks to them about human reaction times and the physics of hurtling automobiles and the harm of sudden impact. He has done this for 20 years, but lately a hush falls over the room as audiences realize that it has become a personal story.

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Twenty-one years ago, Didone knocked at the door of a Damascus home where a mother had just lost a son. She asked Didone whether her son had been drinking and why nothing had been done to stop it.

He felt defensive at first, he says, but “what rang through to me was that everyone had a role.”

Now he’s the director of the police department’s traffic division and gets to most teen crashes. This month, he joined a panel of school, police, parent and community leaders calling for a stronger effort to address teens’ alcohol and drug use in Montgomery. Today, he’s scheduled to appear at a legislative event on Capitol Hill to promote teen driving safety.

His voice of concern is one of many in these weeks of late spring. PTA leaders organize alcohol-free after-prom events. Schools host such programs as “Every 15 Minutes” that dramatize the realities of crashes. Wrecked cars are parked on school campuses.

Many parents hold their breath.

‘Dangerous’ times

In Montgomery, Didone, 52, worries that teens are consuming more alcohol than before and that more parents are allowing parties or condoning drinking. Police see increased alcohol levels — and alcohol poisoning — when they break up underage parties, he said.

The weeks of prom and graduations are a time of great concern because “we know historically that is one of the most dangerous times,” he said.

He takes a long view of teen driving and crashes.

In 1994, a tragedy that many simply refer to as “River Road” had a galvanizing effect. A Walt Whitman High School student who had gotten her driver’s license just three weeks earlier, plowed a BMW into a tree in Bethesda, an alcohol-related crash that left her and another teen dead and two others gravely injured.

Afterward, initiatives about underage drinking gained prominence, with more after-prom events across the county and an array of other efforts that brought together government and community leaders.

For Didone, the crash that killed three young people in Olney last year was a signal that momentum had waned.

In May 2011, a drunk driver struck two trees and a utility pole, ending the lives of three students with ties to Magruder High School: Haeley McGuire, 18; Spencer Datt, 18; and John Hoover, 20.

“The lessons that had been learned have been lost,” Didone said.

This month, Didone met Hoover’s mother at Paint Branch High School. Carolyn Hoover has recently begun telling her family’s story, too.

“It looks like we’re back to where we started 20 years ago,” he told her. “That’s the goal now: to rejuvenate the interest.”

Didone’s police jobs have changed over his long career, but his passion for traffic safety has remained focused on teens and driving. At his office in Gaithersburg, he does not lose sight of the toll. One wall displays a large photo of his son smiling. On another is a photo of the mangled remains of the Volvo.

“You’ve got to realize that life is precious and you can’t let your guard down,” he said.

It was Oct. 20, 2008, when Didone got a call about a wreck on Hawkins Creamery Road in Damascus. His daughter told him that Ryan might be involved, but he refused to think that was possible, he said.

Ryan was an athletic kid who played football and baseball and loved motocross racing. He was big-hearted and outgoing, the youngest of two children who on that night was attending a Christian youth group meeting.

Five teenagers left the meeting in the Volvo, intending to stop at Burger King on the way home. But on a dark road, the driver swerved and was unable to gain control before slamming into a tree.

With his son in an ambulance, Didone walked the scene. When he stuck his head into the car’s bent hulk, the reality about Ryan hit him hard.

“Some of this blood might be his,” he recalls thinking.

He recalls the moment when, at a hospital in Baltimore, a doctor approached the waiting area. Didone, who had broken terrible news to parents many times, recognized the doctor’s expression.

His son would not make it.

Wrecked car spoke, too

The car that claimed Ryan’s life was on display at area high schools for many a prom. The mass of wrecked metal went to Capitol Hill, too, when Didone was part of a legislative event about a bill to expand graduated licensing for teen drivers.

Finally, the Volvo began to rust and fall apart.

But Didone has kept talking. He wove his son’s story into his presentation about teen safety, renaming it “Forever Fifteen” because Ryan will never get older. He wears a bracelet with those words.

“He has tirelessly gone and spoken to whoever asks him to speak— and he did that long before Ryan died,” said Meg Baker, who has known Didone for two decades and is co-president of the Montgomery County Project Prom/Graduation.

Still, the story of Ryan’s crash changes how audiences respond.

“My stomach just dropped,” said parent Jennifer Maroney Tripodi, who heard Didone speak May 7 at Albert Einstein High School. “I felt like if it could happen to him, it could happen to me.”

Didone, the son of a D.C. narcotics detective, married a Rockville police officer and later divorced.

Ryan’s mother, Marlene Didone, is a driver’s education instructor with I Drive Smart, which included Ryan’s older sister, Kara, in a video on the causes of teen crashes and fatalities.

At Paint Branch High, Tom Didone started with a slide about how teenagers are plagued by immaturity, inexperience and feelings of invincibility.

A student heckled.

He talked about texting while driving. He showed a video of what happens when passengers not wearing seat belts are tossed around inside a crashing car — how they can kill or injure one another.

He pointed to a slide of a handsome, happy teenager with an earring.

“This was my 15-year-old son,” he said.

The auditorium fell silent.

Didone talked about how his son climbed into a car with a teen driver who had a provisional license for just two weeks and was speeding. Four passengers were in the car. Ryan did not wear a seat belt — a fact that still confounds his father.

“Ryan never had to be reminded,” he said.

Didone described how severely another passenger was injured. He told them about all that his son will never experience — prom, graduation, college, perhaps a police career.

He asked: What will you do differently?

Teacher Christine Blakely cried. Students sitting nearby teared up.

The Paint Branch prom went smoothly.

Still, more weeks of spring stretched out ahead, with proms largely over and graduation season to follow.

“My hope every time,” he said, “is to get to the finish line with no fatalities or serious crashes.”