There's no single "hardest" crime, but notorious unsolved cases like the Zodiac Killer, the Black Dahlia, and the D.B. Cooper Hijacking are famous for lack of evidence, while some solved cases, like the Maria Ridulph kidnapping, took decades and massive forensic/genealogical work, making them incredibly difficult. Generally, crimes with few witnesses, no DNA, or where the killer left no trace (like poisonings or some burglaries) are the hardest for police to solve, according to crime experts.
Burglary is probably the most difficult to solve because its perpetrators do not have a motive that makes the victim's identity relevant. In most cases, they will elect to steal from an unoccupied home or dwelling, which may leave few, if any, witnesses.
9/11 Investigation
They were the most lethal terrorist attacks in history, taking the lives of 3,000 Americans and international citizens and ultimately leading to far-reaching changes in anti-terror approaches and operations in the U.S. and around the globe.
Crime clearance rate U.S. 2023, by type of offense
In 2023, murder and manslaughter charges had the highest crime clearance rate in the United States, with 57.8 percent of all cases being cleared by arrest or so-called exceptional means.
Murder. Leopold and Loeb, who were 19 and 18, respectively, at the time, settled on kidnapping and murdering a younger adolescent as their perfect crime. They spent seven months planning everything, from the method of abduction to the disposal of the body.
True crime has never been more popular, especially among Millennials and Gen Z. We spoke to devoted fans and one of Britain's leading creators, True Crime Caitlyn, to uncover why these dark stories captivate a new generation.
Other factors that affect crime rate include registration of complaint, cognisance of offence, which differs in different states. Among states, Kerala has the highest crime rate, and Nagaland has the lowest crime rate in 2022.
10 countries with highest crime rate in 2025
Let's start with one of the most publicized unsolved cases, so popular, there's even a website dedicated to tracking this murderer down.
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Dark Crime Series
According to the Rome Statute, there are eleven types of crimes that can be charged as a crime against humanity when "committed as part of a widespread or systematic attack directed against any civilian population": "murder; extermination; enslavement; deportation or forcible transfer of population; imprisonment or ...
The Infamous Cheese Theft
In 2013, a group of individuals carried out what can only be described as an unusual heist. Their target wasn't a bank vault or jewellery shop, but a dairy farm. Under the cover of darkness, they loaded a substantial quantity of cheese—valued at thousands of pounds—into their getaway vehicle.
10 Chilling Unsolved Mysteries That Continue to Baffle...
Theft or larceny is the most common type of property crime. It's estimated that someone is a victim of theft every 5.5 seconds.
The mystery of the Phaistos Disc is a story that sounds like something out of an Indiana Jones movie. 3 Discovered by Italian archaeologist Luigi Pernier in 1908 in the Minoan palace site of Phaistos, the disc is made of fired clay and contains mysterious symbols that may represent an unknown form of hieroglyphics.
How this story was reported. The 1957 kidnapping and murder of 7-year-old Maria Ridulph is the nation's oldest cold case to go to trial. This story was pieced together by CNN's Ann O'Neill through interviews and public records.
25 of the Most Mysterious Deaths in History
Iceland is consistently ranked as the #1 safest country in the world by the Global Peace Index (GPI), a position it has held for over a decade due to extremely low crime, no standing army, high social cohesion, and minimal conflict, though some other reports might place Switzerland or the Netherlands first based on different survey criteria.
What Are the Most Common Types of Crimes in the US?
Top 10 Safest States in America
Crime rate by country 2025: 10 countries with the highest crime...
Memphis, Tennessee had the highest violent crime of 100,000+ population cities, with 2,501 violent crimes per 100,000 residents in 2024. Oakland, California and Detroit, Michigan, followed at 1,925 and 1,781, respectively.