How did 16-year-old honor student Annie McCann die? Her parents have been agonizing over that heart-wrenching question for too long. Definitive answers have been few, but these determined parents refuse to give up asking.

On Oct. 31, 2008, Annie left a note in her bedroom that mentioned suicide, but she had also added the hope-filled line: "But I realized I can start over, instead. ... If you really love me, you'll let me go." Then, she inexplicably ran away, taking $1,000 in cash, jewelry and the family Volvo. It was a shock to Dan and Mary Jane McCann, whose daughter was a devout Catholic, quiet and studious — a child who had never given them any trouble.

Two excruciating days later, the McCanns got a phone call informing them Annie's body had been found at a housing project in Baltimore, about 70 miles from their home. They were dumbfounded.

The Maryland medical examiner ultimately declared Annie's death was due to lidocaine poisoning and concluded she had ingested the bottle of Bactine she carried to treat her newly pierced ears. The company that makes Bactine, along with a well-known medical examiner, Dr. Michael Baden, would both later declare that drinking one bottle would never be fatal.

After reviewing the autopsy and other reports, prominent psychiatrist Dr. Keith Ablow concluded, "It strains the imagination ... to believe that a person intent on dying would choose this obscure and extremely uncertain method of attempting to take her life."

While the official cause of Annie's death is still listed as "undetermined," Baltimore Police Department spokesman Anthony Guglielmi told me this week, "Police believe it was a suicide." Translated: While the case is listed as "pending," it might as well be closed.

The McCanns hired a private detective to figure out how Annie — who always had a lousy sense of direction and hadn't been driving that long — got all the way to Baltimore. P.I. Jimmy Kontsis followed the lead of a fingerprint found on the window of the McCanns' recovered car. That led to a group of local teens who admitted one of their group, a kid named D.J., had stolen the McCanns' car. But each of them insisted Annie was already dead in the back seat, so they tossed her body and took a joyride. Police said they could find no evidence to charge them in Annie's death, and auto theft charges were never pursued, either.

Noting that Annie's autopsy remarked on "fresh injuries to her face and head," Baden suggested Annie might have died from homicidal suffocation. Was she victimized for the $1,000 she took with her? Police made note of Annie's clean white socks but could never find her shoes. Might they have been left at the same place she ingested the lidocaine?

"That's the mystery," Kontsis told me. "Even the police were, like, lidocaine? They didn't get it, either." Drug addicts have been known to try to smoke lidocaine, but Annie never experimented with drugs. Classmates called her sheltered and naive.

Kontsis canvassed people at spots where Annie had been — her church, a Virginia Costco, even a pastry shop in the Little Italy section of Baltimore. He discovered a consistent description of an older, apparently homeless Hispanic woman seen speaking with Annie at all three locations. A sketch of the mystery woman (who claimed to be from Honduras and was seeking immigration information) brought in no helpful information.

And then, last November, the teenager known as D.J. — real name Darnell Kinlaw, now 21 — was arrested in Baltimore for murdering a woman and stealing her car. It was revealed that Kinlaw's extensive police record lists eight charges of auto theft. Annie's parents figured it was the perfect time to get more information from Kinlaw about the day their daughter died.

The McCanns travelled to meet Baltimore police, and while they were treated politely, they feel they have been lied to and ignored. Police say they are sympathetic but maintain they've already conducted a thorough investigation.

Look, maybe Annie McCann did manage to get a stash of lidocaine and poison herself. But that seems unlikely, and after researching this case and counting up the loose ends — the odd trip to Baltimore, the missing money, the mystery woman and Kinlaw's past — I can't help but feel that in the absence of concrete evidence, Annie's half-used Bactine bottle gave police a convenient reason for her death. Easier to declare it a suicide and move on. Left in the wake of that decision are Dan and Mary Jane McCann, who cannot find peace. They still wonder why they never got Annie's clothes back and why no one will tell them whether she had been raped the day she died.

The sad fact is there are countless families mourning the loss of their murdered children every day in America. They are black, Hispanic, Asian and, in the case of Annie McCann, white. Their tears are all the same color.

In the end, it really isn't race or ethnic background that matters when a child is murdered. It is the feeling families often get that no one cares enough to find the truth — that there will be no justice — that hurts so much.

Maybe our overburdened, understaffed police departments can find some way to work on making families feel more included in the heartbreaking process of homicide investigation.

Visit Diane Dimond's official website at www.dianedimond.com for investigative reporting, polls and more. To find out more about Diane Dimond and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.