A constant force in the Tulsa Police Department's ability to solve violent crimes is Sergeant Dave Walker.
The lead homicide detective has been on the force more than 30 years and has seen his share of tragedy.
He's set to retire with one of the highest homicide solve rates in the nation.
Anchor Scott Thompson sits down exclusively with the sergeant to talk about what gets him through those hard times.
Dave Walker sees a lot of death.
Baseball helps get him through it, so does a faith that pure evil is still very rare.
And there's that smiling photo that sits atop a messy desk.
Every time someone dies at another's hand in Tulsa, Dave Walker shows up to try to figure out who, and why.
"There is a reason why this person's dead," Walker said. "And it's your job is to go find it."
In the seven years he's overseen the Tulsa Police Department's Homicide Division, Sergeant Walker, and the detectives who share the office with him, have had to find over 450 reasons why.
It's not rocket science, really, solving murders is not rocket science, it's taking one thing, going here, and ok, this lands you over here, and eventually you get there.
They've gotten there over 95 percent of the time, one of the highest solve rates of the country's big-city police departments.
But what's the toll on a man?
One who shows up at every murder, no matter the day or time.
Who sees the absolute worst of humanity, week after week, and lives with it 24 hours a day.
"You have to care about this, so we learn early on your care," Sgt. Walker said. "If you don't care, you're not gonna be doing this 24 hours a day. It's that caring ability to just work until you get it done and not allowing no answer to be the answer."
For years, I've watched the video of him walking about, usually with a clipboard or notepad, ducking beneath crime scene tape, and wondered how he faces one bloody scene after another.
Turns out, by the time the camera's capture him here, he's already taken the time to consider not only what's just happened, but what's about to come.
"I personally will take a minute, 30 seconds, whatever, go away and realize, 'wow, somewhere along the line we're gonna have to tell somebody their loved one is dead and that's gonna be a bad deal,'" Walker said.
There are nine of them here on the sixth floor of police headquarters, surrounded by shelves-full of sadness.
The lives whose tragic ends intertwined with theirs, because a bad decision was made, a wrong path followed.
"Yeah, decision making is a big part of victimology," Walker said. "Our victims made a bad choice somewhere along the line."
Others just had the bad luck to run across evil.
Though Sergeant Walker insists, after all, he's seen, that pure evil is not a common human trait.
"What I have to say is, there are so many more of the good people than there are of the true evil that this world is so much better off," Walker said.
He's got a few things that temper the terrible.
Grandkids are good for that.
"Baseball's a big part of how I keep mind off what we're doin' out here," Walker said.
And on a floor filled with the stares of sadness, in his messy office, atop a messy desk, is a smile - his wife Johnnie's.
"She can feel the same compassion, and she can put herself in the family's spot," Walker said. "She will tear-up when you talk about some of the cases."
Johnnie and Dave have been together 21 years.
She helps get him through it.
"Sometimes it's a grind because you're done here and we go home and have to explain what we did at work today, but she's very understanding when it comes to that," Walker said. "Are you a man who shows your emotion very easily? I wonder does anything you see ever make you cry? Scott, I knew you were probably going to ask that question, and to answer that, we cry alone."
They cry alone.
In a room filled with tear-stained stories, they cry alone.
"That's just the way it is," Walker said.
At least publicly, Sergeant Walker hasn't set a firm retirement day.
Stay in touch with us anytime, anywhere.
Sign up for newsletters emailed to your inbox. Select from these options: Breaking News, Severe Weather, School Closings, Daily Headlines and Daily Forecasts.