Houston's murder rate ranked 46th of U.S. cities with a population over 250,000 in 2005 (per capita rate of 16.3 murders per 100,000 population). The city's murder rate was ranked in 2005 to be third among U.S. cities with a population of over 1,000,000. This ranking could be higher as KHOU-TV found the Houston Police Department under-counted 2005 homicides; counting two more would have bumped up the rate to second place.
While nonviolent crime in the city dropped by 2 percent in 2005 compared to 2004, homicides rose by 23.5 percent. Since 2005, Houston has experienced a significant rise in crime, which the Houston Police Department partly attributed to an influx of people from New Orleans following Hurricane Katrina. After Katrina, Houston's murder rate increased 70 percent in November and December 2005 compared to levels in 2004. The city recorded 336 murders in 2005, compared to 272 in 2004.
Houston's homicide rate per 100,000 residents increased from 16.33 in 2005 to 17.24 in 2006. The number of murders in the city increased to 379 in 2006. The Times-Picayune disputed that Katrina refugees were to blame for the rise in crime, citing statistics that crime was rising in Houston before their arrival. City officials claimed that though the majority of refugees were law-abiding citizens, Houston's population swelled by 10 percent "virtually overnight," reducing the ratio of police officers to citizens.
A 2010 study published in the Journal of Criminal Justice also disputed the assertion that Katrina refugees were the cause of rising crime in Houston around the mid-to-late 2000s decade, and instead pointed out factors such as growing population, rising unemployment, and decreased police patrol.
Houston—due to its size and proximity to major illegal drug exporting nations—is a significant hub for trafficking of cocaine, marijuana, heroin, MDMA, and methamphetamine.
In 2007, Houston ranked first for auto-theft in the state of Texas when more than 31,000 motor vehicles were stolen in the metropolitan area.
In 2010, the area within Houston with the least amounts of crime incidents was at the intersection of Westheimer Road and State Highway 6.
In the early 1970s, Houston, Pasadena and several coastal towns were the site of the 'Houston Mass Murders' which at the time were the deadliest case of serial killing in American history.