Without a body, proving that someone has committed murder is difficult but not impossible. More than 500 no-body murder trials have been held in the United States, with a conviction rate higher than that of all murder trials.

The U.S. originally started the federal witness protection program to protect people from the mob. And the people who received protection? They were usually part of the mob too.

In today's world, homicide detectives are expected to be jacks-of-all-trades: equally adept at chasing outlaws and identifying DNA evidence at the scene of the crime. But, in an overwhelmingly male-dominated field, Frances Glessner Lee, a Midwestern woman without a high school diploma, made contributions throughout the 1930s and 40s that earned her the moniker 'The Mother of Forensic Science.'

A&E True Crime speaks with Anne E. Schwartz, a former crime reporter for The Milwaukee Journal, who broke the story about Jeffrey Dahmer's arrest on July 22, 1991, about what it was like uncovering the life and murders of one of America's most notorious serial killers.

You may have heard about body farms, the research facilities where people donate dead bodies for scholarly research. But have you ever wondered what goes on in these places? What exactly are scientists doing with all these donated bodies? What mysteries are they trying to solve, and why?

Sex trafficking is big business. Globally, it generates tens of billions of dollars in profit every year. Here in the United States, it ensnares hundreds of thousands of victims. And while the stereotypical image of a trafficking victim is a foreign national, many of the exploited are underage American girls.

By the time Nassar was sentenced to 60 years in federal prison, his accusers numbered in the hundreds⁠—mostly athletes training and competing under the auspices of USA Gymnastics.

Christopher Bernard Wilder became known as 'The Beauty Queen Killer' during a frenzied 1984 spree, where he criss-crossed the U.S., luring young women into his fancy cars and dangling the promise of work as a model, if they would just allow him to take their photographs. Some took the bait. Others, he took by force.

Dominick Polifrone gained the confidence of the contract killer in an undercover operation that almost cost him his life.

For nearly two decades, Chicago faced a curious rise in the number of unsolved murders against women involving strangulation—all in certain areas of the city. We take a look at one of the unsolved cases and what police are doing to solve the string of murders.