Cold-case killing suspect diesSecond arrest made in 17-year-old slayingSecond arrest in Horton caseMom: Son was killed after discoveryFamily unaware of Glidden's involvement in son's deathFamily surprised by latest arrest4th suspect in sailor's slaying arrested in N.J.2 slaying suspects back in S.C.Suspect to be brought to S.C.Extradited murder suspect faces Berkeley judgeFourth suspect in killing faces judge4 denied bond in killing5th arrest in sailor slayingEx-suspect seeks justice, but not at his expenseKonnie Glidden says her confession in the 1992 cold case murder of James Horton in Berkeley County was pack of liesKonnie Glidden seeks to have confession tossed out in cold case murderSuspect wants confession ousted Glidden accused in 1992 killing of sailorCold-case murder suspect gets hearingAttorney says she’ll fight to clear client Glidden’s name

SUMMERVILLE — Gloria Boone remembers hearing two pops that night nine years ago — the sound of the gunshot that pierced a car windshield, and the other bullet that sank into her youngest child's chest.

Then, she heard a deep chuckle.

“I heard this laughter,” she remembers. “It sounded like the devil.”

The devil, whoever it was, killed 21-year-old David Boone as he listened to music in his old gray Nissan right there in his parents' driveway on Pawley Drive. Then the devil left in a white truck.

That's all the Boone family knows, though they suspect someone out there knows more.

“We can remember exactly what happened that day,” said David Boone's sister, Antawon, who went out with her three young children to find her little brother collapsed and dying near his car.

“We can even remember what we were wearing. If we remember, there are other people who remember.”

David Boone's case is Summerville's only unsolved killing. His death numbers among dozens of so-called cold cases around the Lowcountry, investigations that never turned up enough evidence to make an arrest at the time. So, time passed.

Talking about David, his mother said, is like digging him up and burying him again. Yet she and her children talk, in hopes that someone will remember that night and will decide to talk too.

People around town knew Boone as the neighborhood grass-cutter, the kid who entered the Alston Middle School talent show as a drummer but had only buckets to play — and won. Not only did his death gnaw at his family and community, it stuck with the investigator assigned to solve it.

When the detective died a few years after Boone did, he was buried with Boone's photograph in his coat pocket.

Cold cases haunt the living across the Lowcountry. Detectives come to know families of the dead, and the relatives and investigators often grow old together as years pass without resolution.

The Charleston County Sheriff's Office lists seven unsolved or active murder cases since 2006, while Berkeley County counts none so recent, and Dorchester County has two open cases. The North Charleston Police Department lists 26 active cases since 2006, and the Charleston Police Department has 18 unsolved killings.

Those Charleston city cases include David Boone's uncle, John Jenkins, a Vietnam War veteran who died homeless, gunned down in the early morning hours in front of St. John's Episcopal Church in 2010. Residents in the East Side community knew the 67-year-old Green Beret as “Pap,” who, despite his own circumstances, mentored boys in the community that he called “the village.”

Gloria Boone said she asked her brother to move in with them in Summerville, to come in off the streets. He told her he couldn't, that he had to wait for his orders.

“He was always in the jungle in his mind,” she said.

Gloria Boone's brother met the same fate as her son, a name on a file that torments families and frustrates detectives.

All Charleston city cold cases until 2007 fall to the hands of Sgt. Mike Gordon, who retired from the department in 2008, then came back to work unsolved murder and rape investigations, thanks to federal grant funding. He and a small group of volunteers pore over files dating to 1969, focusing on those cases with strong physical evidence.

In some cases, new technology for DNA testing could redirect old, otherwise stale investigations. Gordon said he spends much of his time these days looking into the murders of five young black women killed along the King Street corridor in the 1990s, all found dead in abandoned homes or behind isolated buildings with evidence of sexual assault.

Gordon invests in the idea that people change over time. Divorces shift alliances, and criminals doing time on other charges might speak up about old cases in order to strike a deal with prosecutors.

“A lot of things can happen to witnesses, to suspects, that might make them more inclined to talk now than they were 10 or 15 years ago,” Gordon said.

Detectives with the Dorchester County Sheriff's Office keep copies of their unsolved killings in their cruisers. Lt. Tony Phinney said they flip through the pages, trying to shake loose new ideas in their downtime.

“We kind of live with it,” he said.

His department's most active cases include the nearly 13-year-old case of Stephanie Thompson, a 42-year-old woman found strangled and partially nude in some woods near an industrial park.

Detectives also still push for new clues on the 1980s abduction case of two women, Linda McCord and Sarah Boyd, and Boyd's toddler daughter, Kimberly, last seen heading home from a gospel concert in Walterboro.

At the Charleston County Sheriff's Office, detectives work cold cases on slow days, and two part-time deputies focus only on unsolved cases. Sgt. Derek Boyd said a case remains active until the leads dry up.

Then the detectives meet to exhaust all possibilities. After that, they meet with prosecutors or state investigators before declaring the case inactive.

Perhaps the most high-profile unsolved case in recent memory, 5-year-old Allison Griffor's October shooting death, remains very much active, Boyd said. Investigators continue working a few strong leads, he said, and Sheriff Al Cannon announced last month that federal authorities had taken a role in the case.

Jennifer Griffor, Allison's mother, keeps tabs on the investigation through regular contact with a victim's advocate. The frightened family moved out of state after the shooting, but calls investigators to check in on the case from time to time.

“We're trying to live our lives, and then, when we start to feel really sad and curious, we will call them,” Griffor said.

Allison was shot through the family's front door in West Ashley as she slept in her bed near her two brothers, ages 7 and 2 at the time. The family moved and bought new furniture, and Jennifer Griffor found a job, but life is far from normal with their middle child's case unsolved.

Jennifer Griffor said her husband struggles with telling people about where they are and what they are doing while the killer remains at large. He also hasn't been able to pull a steady paycheck.

“We're probably going to have to rely on family again until he finds work,” Jennifer said. “We had hopes to move forward, but it didn't go the way we wanted.”

Gloria Boone, David Boone's mother, understands that challenge of moving forward. Her family has left town every Christmas since her son's death, to get away from the house where he died, yet she talks to him before each trip.

“Come on, David,” she says, as the rest of the family heads out for vacation.

David Boone would have been 30 years old this summer, but nearly a decade after his death, his mother still cannot look at his photograph.

But Gloria Boone wonders what her son would look like now. What he would be doing now.

Reach Allyson Bird at 937-5594 or Twitter.com/allysonjbird.