In very rare instances, people who suspect their fathers, brothers or other family members are long-sought serial killers are dead right and help authorities solve a notorious cold case. But far more often, they pester police with circumstantial evidence backing up wild theories.

In the early 1970s, Rochester, New York was plagued by a series of unsolved child murders. The three victims each had alliterative names and the killings became known as the 'double initial' or 'alphabet' murders. Will the killer or killers ever be found?

Genealogical DNA databases are helping solve more cold cases. We explore why that could be problematic.

There's been no shortage of violent crime this decade, either. As the 2010s come to a close, A&E True Crime looks back at the past 10 years—at some of the crime stories that drew the most public attention, and at the criminals the public will long remember.

Police have solved, or are close to solving, a number of cases that have been cold for decades. Investigators are using new technology and research techniques and re-examining leads that previous investigators may have ignored.

In the mid-2000s, girls and women started disappearing. A few years later, their bones turned up in a grave—but some are still missing.

Ethan Brown, a reporter who spent years investigating the murders of eight sex workers in Jennings, Louisiana and wrote the book 'Murder in the Bayou,' says there's credible evidence to suggest that several offenders have blood on their hands, and that Jefferson Davis Parish's own law enforcement may be implicated in the crimes.

Julie Williams, Lollie Winans, Paul Fugate and others are among those who have been killed in national parks and whose cases have yet to be solved.

True-crime writer Billy Jensen empowers readers to become citizen detectives, using social-media resources to identify uncaught criminals. He explains how he does this without interfering in police investigations and tells us about his book, 'Chase Darkness With Me.'

Ken Rex McElroy, a bully who menaced the farming community of Skidmore, Missouri for years, was shot and killed on July 10, 1981 outside a local bar. Witnessing the murder were McElroy's wife and dozens of local residents. Yet the gunman has never been identified.