This week’s news that someone has been charged with the 3-year-old murder of Willie Christie, a popular custodian at Fairmont Middle School, should bring smiles — and relief — to that tight-knit community. Since Christie’s brutal slaying in May 2008, Fairmont residents couldn’t help but wonder if the murderer were still walking among them — and if he would strike again.

Now they can confidently set aside that worry.

The man accused was living in Fayetteville, but was a former resident of Fairmont. According to police, Christie employed 31-year-old Johnny Terrell McKoy in a landscaping business he operated when he wasn’t cleaning up behind middle school students. On Tuesday, during a press conference by Fairmont police, Christie was even described as a “mentor” to McKoy.

Police played their cards close to the vest during the press conference, not wanting to jeopardize an investigation that seemingly hangs on a single piece of compelling evidence — that McKoy’s blood and DNA were found at the murder scene. If a case were to hang by a single string, it could not be much more tenacious than blood and DNA evidence, assuming that when the trial comes, the jury isn’t the one that freed double-killer O.J. Simpson.

Since Christie’s murder, Fairmont police have been aggressive in their efforts through the media to assure the public that this case had not grown cold, and that there was evidence that they believed would lead to the arrest and conviction of the person who killed Christie. The implication, which was clear at the time, is now crystal clear: Police had DNA and blood evidence that only needed to be matched.

The mystery is why did it take so long to make that match. According to Fairmont police, McKoy became a person of interest about eight months ago following a tip, and that led to a comparison of his blood and DNA with what was collected at the murder scene. But McKoy has a criminal history that dates to 1997, so his DNA should have been in a data base for a match to have been made. We know this is the real world, not “CSI,” but the pieces were there — and the opportunity exists to shore up a hole in the state’s network of comparing DNA samples.

Police say McKoy isn’t talking, and they still don’t have a motive for Christie’s murder. Eventually that, too, will be known. And we will know that yet another fellow Robesonian has been murdered for no reason at all.