Incentives for corrupting police and other public officials occur at all stages of narcotics trafficking, from importation through prosecution. Corruption among police in this area may involve selling protection or sensitive information to traffickers, acting as a courier, or dealing drugs. Often corrupt police have links with corrupt judges and prosecuting attorneys as well. Proactive investigations, using informants and undercover agents, are most effective. Historical cases can be made, but require extensive corroboration of informant-witness testimony. Because of the lavish amounts of money often involved, financial investigation showing a lifestyle incompatible with that of an honest police officer also may be effective. Successful investigation requires the coordination of efforts, including designation of a special corruption squad or task force, development of a central intelligence base for corruption allegations, and the use of local police internal affairs resources. In addition to the customary corruption statutes (e.g., bribery, Hobbs Act), an arsenal of narcotics-related statutes are available in prosecuting such cases.