Which form of arson evidence is most commonly submitted for analysis?

The form of arson evidence that is most commonly submitted for analysis is solid debris suspected of containing volatile liquids. This is primarily because the identification and analysis of volatile substances are crucial in arson investigations. When a fire is set intentionally, accelerants such as gasoline or other flammable liquids may be used to facilitate ignition and spread.

Solid debris, including materials like wood, fabric, or other combustibles, can retain residues of these accelerants, making it possible for forensic analysts to extract and identify them through various chemical analysis techniques. This evidence can be pivotal in determining whether a fire was caused intentionally and can provide significant leads in an investigation.

While liquid samples are also important, solid debris is more frequently encountered in fire scenes as it is more common for accelerants to be absorbed into various materials than to find liquid samples left behind after a fire. Additionally, clothing from witnesses may be relevant in relation to witness statements or victim analysis but does not directly pertain to determining the cause of the fire. Fire patterns, although useful in understanding how a fire spread, do not provide direct evidence of the means used to ignite it. Therefore, solid debris containing volatile liquids represents the most practical and frequently submitted evidence type in arson cases.