It is accepted that a person with knowledge that a crime, or some other form of abuse, has been committed should convey that information to appropriate authorities in order that remedial measures may be taken and justice done. Where the authorities are themselves perceived as unjust or the abuse is defined by laws or regulations which are perceived as unjust, the informer is viewed as acting against the interests of the social group within which the so-called abuse took place. Informers are especially suspect when they act not for the promotion of the welfare of the society, however it is defined, but for payment or in a spirit of personal revenge. The negative consequences of their activities are increased when the information conveyed is false or deliberately misleading and when authorities actively encourage people to inform against each other.
Informers have existed in most cultures. The difficulties they create were recognized in the Code of Manu and especially from the early Roman Empire. Extensive use of networks of informers has traditionally been made by despots, dictators and repressive regimes. Their use has been encouraged in occupied countries and territories as a means of controlling the population and establishing a reign of fear. Such informers are subsequently judged as traitors to their country. Networks of informers have acquired a more organized form on the initiative of modern intelligence services.
Withholding information which could remedy an abuse or bring a criminal to justice makes a person party to that abuse. In many cases informers advance the cause of law and order when otherwise crime would flourish. Often the use of informers is the only means to break criminal networks and to prevent subversive or terrorist activities.
Confidential sources are the bastard children of official secrecy; in a genuinely open democracy, they would not need to exist. But while governments, armies and police forces continue to conceal truths of significance to the public, the confidential source, the mole, the leaker, are all that stand between the public and a totalitarian society.
In order to curtail financial fraud, regulatory bodies, such as in the UK in 1993, may encourage investors and investment industries to report anomalies: "Be a whistle blower, whether you are a private or professional investor, or even if you work in the industry, if you think that there is something fishy about an investment firm, tell its regulator".
Whistleblowers are public-people who are prepared to put the interest of others first, even when this might entail considerable personal risk.