A criminal investigation conducted by a fire or police department is confidential, so any information obtained in the investigation cannot be released to any outside source until the case is closed or a person has been arrested and convicted of arson. Insurance companies must therefore rely upon private investigators to determine whether a fire insurance claim is valid. The primary role of the private investigator in arson investigation is to provide the insurance company with the information needed to determine whether to deny or pay the claim. The product of any private investigation funded by an insurance company is the property of the insurance company, but may be shared with police investigators. Where there has been such cooperation, an increase in the successful denials of insurance claims and in the amount of arrests and convictions has occurred. Federal intervention in arson investigations occurs through the ATF under the authorization of the Gun Control Act, which requires that certain 'destructive devices' frequently used by arsonists be registered with the Secretary of the Treasury to be legally possessed, and Title XI of the Organized Crime Control Act, which provides criminal sanctions against persons charged with the destruction of certain types of property with 'explosives.' The ATF uses national response teams that have the capability of providing a 24-hour response to any location in the United States to assist in the investigation of significant arson or explosives incidents.