Seminar tracks cases where trail's gone cold

ANNAPOLIS, Maryland (CNN) -- A missing intern. A murdered child beauty queen. The slain wife of a film and TV star.

The cases of Chandra Levy, Jon Benet Ramsey and Bonny Lee Bakley have routinely commanded headlines as investigators continue following trails that grow more faint with each passing day.

Yet those cases are but a few police investigations in which leads have dwindled or dried up. In just the United States Navy and Marine Corps, say military officials, investigators are confronted with some 80 cases where the trail has grown cold, the clues scarce.

Those cases drew criminal investigators to the U.S. Naval Academy on Tuesday, where military and civilian specialists met to share strategies for solving "cold cases" that were not quickly solved. More than 120 law enforcement officials gathered for the four-day event, organized by the Naval Criminal Investigative Service, to discuss breakthroughs solving such investigations, most of them homicides.

"In each one of these cases, we sit down and we actually go through each interview. We analyze what is going on, and everything is carefully planned out, every step," said Jim Grebas of the Navy's cold-case unit. He was interviewed on CNN Tuesday.

Against the backdrop of missing intern Levy -- and with other high-profile, unsolved cases that include the may murder of Bakley, wife of actor Robert Blake, and the slaying in 1996 of 6-year-old Jon Benet Ramsey -- forensic scientists, a psychologist, an FBI profiler and other experts were among those to describe their techniques.

Other specialists shared tips on how better to deal with victims' family members.

"Time is our ally," Grebas said. "It gives us time to methodically go through these cases, re-activate them and focus on our suspects."

The Naval Criminal Investigative Service began its cold-case unit in 1995, and has since solved 33 cold cases. The group is now trying to crack some 80 other investigations involving U.S. Navy or Marine Corps matters.

"The difficult part in these investigations is getting those reluctant witnesses or former spouses to now cooperate," Grebas said. "We have to ensure their safety, number one, and that's where the strategy comes in, in the planning of attacking these cases."

33-year-old case solved

The Annapolis event, the second annual gathering, draws participants from state and local police departments as well as federal law enforcement officials. The seminar began after investigators reopened and solved a cold case dating back 33 years.

In November 1968, 19-year-old Anne Bradley, a student at St. John's College here, was shot and killed on a park bench outside the Maryland Statehouse. Police believed the murder occurred during a robbery, but could not gather enough information to charge a suspect.

In 1992, the Anne Arundel County State's Attorney Office formed a so-called cold-cases unit and took another look at the Bradley case. In 1993, an investigator found evidence that pointed suspicion toward a man who had died from a drug overdose in 1985.

After gathering more evidence, police said they believed the dead suspect -- Alonzo Henry Johnson Jr. -- had committed the 1968 murder, and the case was closed in November of 1995.

Organizers of Tuesday's cold-case seminar hope to use the Bradley murder as an example of how to reopen and perhaps solve cases once thought to be hopeless.