Contract killing is a form of murder or assassination in which one party hires another party to kill a targeted person or persons. It involves an illegal agreement which includes some form of payment, monetary or otherwise. Either party may be a person, group, or organization. Contract killing has been associated with organized crime, government conspiracies, dictatorships, and vendettas. For example, in the United States, the Jewish-American organized crime gang Murder, Inc. committed hundreds of murders on behalf of the National Crime Syndicate during the 1930s and '40s. Contract killing provides the hiring party with the advantage of not having to carry out the actual killing, making it more difficult for law enforcement to connect the hirer with the murder. The likelihood that authorities will establish that party's guilt for the committed crime, especially due to lack of forensic evidence linked to the contracting party, makes the case more difficult to attribute to the hiring party. Contract killers may exhibit serial killer traits, but are generally not classified as such because of third-party killing objectives and detached financial and emotional incentives. Nevertheless, there are occasionally individuals that are labeled as both contract killers and serial killers. A contract killer is colloquially known as a hitman. Contract killers who work for criminal organizations are often known as enforcers. Statistics A study by the Australian Institute of Criminology of 162 contract murders and attempted contract murders in Australia between 1989 and 2002 indicated that the most common reason for murder-for-hire was insurance policy payouts. The study also found that payments varied from $5,000 to $30,000 per killing, with an average of $15,000, and that the most commonly used weapons were firearms. Contract killings accounted for 2% of murders in Australia during that time period. Contract killings generally make up a small percentage of murders. For example, they accounted for about 5% of all murders in Scotland from 1993 to 2002. Notable persons Perpetrators Vincent "Mad Dog" Coll, an Irish-American hitman from Gweedore, County Donegal, who worked for Salvatore Maranzano, Dutch Schultz, and Owney Madden. Elmer "Trigger" Burke, notorious hitman and supporting player in the Great Brink's Robbery Maia "Mainha" Cunha, a notorious Brazilian hitman, he is considered the biggest hitman in Northeast Brazil and his targets were usually northeastern politicians, mostly mayors of cities in the interior of northeastern Brazil. Glennon Engleman, American dentist who moonlighted as a hitman. Ray Ferritto, Italian-American