In general, arson, is the crime of maliciously, voluntarily, and willfully setting fire to the building, buildings, or other property of another, or of burning one's own property for an improper purpose, such as to collect insurance.
The prosecutor must prove each element beyond a reasonable doubt.
Eighteenth-century common law punished arson as a felony. However, it did not regard the destruction of an unoccupied building as arson, "[s]ince arson protected habitation, the burning of an unoccupied house did not constitute arson" and further, "[t]he burning of one's own dwelling to collect insurance did not constitute common law arson. It was generally assumed in early England that one had the legal right to destroy his own property in any manner he chose."
Arson charges are prosecuted with attention to degree of severity in the alleged offense: First-degree felony arson is usually charged when persons are harmed or killed in the course of the fire, second-degree felony arson when significant destruction of property occurs, and so forth. Arson is also variously prosecuted as a misdemeanor or "criminal mischief" or "destruction of property." If the arson involved a "breaking and entering", the second charge of burglary is usually attached. It is possible for the death penalty to be applied in cases where arson is deemed to be a method of homicide, as was the recent case in Texas of Cameron Willingham.
The possibility of financial gain often drives arsonists to file fraudulent insurance claims after setting a fire. Indeed, the most common motive for arson is profit.
Some arson is committed in an effort to conceal or disguise other crimes. Some may be committed by 'enforcers' of protection rackets as consequences of failing to pay extortionists.
Revenge drives some arsonists. Victims’ property is often damaged or destroyed, compromising physical safety and sometimes causing personal injury. Domestic violence sometimes results in arson. Firefighters are occasionally found to have committed arson, with motives including revenge, pyroterrorism or pyromania.
Anger and frustration are behind the arsons perpetrated by juvenile vandals. Vandalism through fire often occurs in vacant or abandoned buildings - for instance schools. Cities usually encourage owners to secure vacant buildings. Fire departments aggressively attack fires in abandoned buildings out of concern for the transient or homeless people that may be dwelling inside.
Political ideology motivates some acts of arson. For example, some members of the Earth Liberation Front are believed to have set fires to structures in order to spread a message of environmental protection. And in virtually every human conflict/war throughout history, acts of arson have been committed or attributed to each side of the conflict, such as in the American Civil War, Kristallnacht - crystal night - pogroms in Nazi Germany in 1938 when ~1000 Jewish synagoges were burnt or most recently, Serbian protests of Kosovo's Independence, at the Serbia-Kosovo border on February 19,2008 and at the American Embassy in Belgrade on February 21,2008.
It was rumored that Roman emperor Nero purposefully ordered the Great Fire of Rome, which erupted on the night of July 18, 64 CE. In reality, the fire started from the shops selling flammable goods at the southeastern end of the Circus Maximus and reportedly lasted for nine days.
Political power motivates others, such as the notorious Reichstag fire of 1933, when the main parliament building in Germany was burnt to the ground. A young Dutchman, Marinus van der Lubbe was found in the building after the fire had started, and he confessed to the deed. However, recent research in the Gestapo archives has shown that the Nazis were actually responsible and used the boy as a scapegoat. A part of SA storm-troopers entered the building along a tunnel from Goering's Presidential palace and set fire to the central chamber using self-igniting mixtures. It is clear from the original fire investigation that no single person could have started so many small fires in the short time available.