Original sentence: Crime rates in the United States are similar to those of other developed countries.Criminologist Gary Kleck compared various survey and proxy measures and found no correlation between overall firearm ownership and gun violence.Gun violence, however, often played a role in these riots (see Haymarket riot).Homicide rates in cities such as Philadelphia were significantly lower than in modern times.Nonetheless, many developing countries have significantly higher rates of homicide and in some cases, firearm usage in homicides, including Mexico, Brazil, Thailand, Guatemala, Colombia, Estonia, and Russia.The rise in crack cocaine use in cities across the United States is often cited as a factor for increased gun violence among youths during this time period.While people during the 19th century were concerned about violent crime, it often took the form of riots and other forms of disorder in cities
Edited sentence: Criminologist Gary Kleck compared various survey and proxy measures and found no correlation between overall firearm ownership and gun violence.. This study was contradicted by David McDowall's study.In 2004, 11,344 people were murdered by guns in the US, but only 184 in Canada, 56 in Australia, and 37 in Sweden.People murdered by guns in the United States are much higher than those of other developed countries.See below for more detail