Missing boy.

Police are investigating the disappearance of Dontrell Melvin, at center, as a homicide case. The boy was last seen in July 2011. His parents, Brittney Sierra, at left, and Calvin Melvin, at right, have been arrested in connection with his disappearance, police say. (Dontrell Melvin, handout photo / Photos of parents by Rafael Olmeda, Sun Sentinel / March 1, 2013)

As investigators gathered around, a tiny skeleton that may solve the mystery of a missing Hallandale Beach boy was laid out on the laboratory table, as delicate and fragile as hand-blown glass.

Conducting the informal Jan. 25 seminar in the Collier County morgue was noted forensic anthropologist Heather Walsh-Haney, who two weeks earlier had helped police unearth the body believed to be that of Dontrell Melvin.

"It was fascinating to see how the remains were put back together," said Hallandale Beach Police Chief Dwayne Flournoy. "We were hanging on her every word."

But now an observation made by the Florida Gulf Coast University professor and recorded in a police detective's notes may complicate the investigation into what happened to Dontrell, who was five months old when he vanished in July 2011.


Photos: Seminole Hard Rock Winterfest Boat Parade

A reference to "post-mortem blunt trauma to the cranium" that "had probably occurred during the search and recovery of the skeleton" has damaged any potential homicide case against Dontrell's parents, said the attorney for the boy's father.

"I don't know if this has implications yet, but it could," said Edward Hoeg, who represents Calvin Melvin, the father of Dontrell. "But obviously, if you destroy and alter evidence, who's to say? It could have consequences for both sides."

Melvin, 27, and the boy's mother, Brittney Sierra, 21, have both been in jail since January in connection with Dontrell's disappearance, authorities say.

Flournoy denied Friday that any post-mortem damage to the remains would compromise a prosecution. "It would just be something you would have to answer at trial," he said. "You would just have to offer an explanation."

Police have not alleged that blunt trauma was the cause of the child's death, said Flournoy.

Dontrell's disappearance did not come to light until child welfare investigators responded to a child neglect call on Jan. 9 this year and found only two children when there should have been three, officials said.

At first Sierra and Melvin told various stories about Dontrell's whereabouts, pointing fingers at each other, said police.

In one statement, Melvin told detectives that he had not seen the boy since July 2011, when he left the house at 106 NW First Ave. after a heated argument with Sierra, police said.

When he returned three weeks later, "Brittney told Calvin that she had done something wrong; but she would not specifiy what she did," according to one police report.

Melvin has since been jailed in lieu of $151,000 bond on charges of giving false information to a law enforcement officer regarding a capital crime. Sierra has been locked up on two counts of child neglect resulting in bodily harm. Her bond is set at $100,000.

Neither parent is charged with homicide, and positive identification of the remains found in January is pending DNA analysis.

Sierra has two other children, including one fathered by Melvin. In recent years DCF officials reported investigating dozens of hotline complaints involving both Sierra and her mother, Renee Menendez, who was raising four children.

Yet no agency had realized that Dontrell was permanently gone.

Once he was declared missing, DCF took all six remaining children and placed them in a state home.

The backyard hunt for Dontrell was triggered by Melvin, who drew a diagram showing a spot bethind the small green house where he might have been buried, according to police reports. The initial search was conducted by the Broward sheriff's crime scene unit, according to police, with an assist from a Miramar police K-9 unit.

At one point a backhoe was used, but only after the remains were recovered, police said.

Walsh-Haney, who has appeared on cable television's Nancy Grace show and worked other high-profile cases, was called in by the Broward medical examiner after the first bones were discovered.

During Walsh-Haney's presentation to investigators in January, she said that "over 90 percent of the baby bones were recovered," a police detective noted.

In addition to Flournoy, those attending were police detectives and Thomas Steinkamp of the Broward Medical Examiner's Office, according to police.

"It was a tremendous learning experience," Flournoy said.

Following that presentation, Flournoy said Walsh-Haney and Broward Medical Examiner Craig Mallak decided to bypass the Broward sheriff's crime lab and send a portion of the remains to the Center for Human Identification at the University of North Texas in Fort Worth.

The process used by the Broward Sheriff's Office would have required pulverizing bone to extract DNA, Flournoy said. "We had some concern with that, so we consulted with the State Attorney's Office and decided, let's try to keep bones intact. It's a better system."

Melvin and Sierra are scheduled back in court May 16.

mwclary@tribune.com, 954-356-4465