An allegation is a claim of wrongdoing which can be made by a third party or by someone who believes that he or she has been wronged in some way. For example, a newspaper could allege that a government agency is not following its own policies when it comes to enforcing regulations, or someone could claim that a neighborhood resident broke a window in a home. Generally, allegations are made when the alleging party believes that the allegation is factually true and that information can be mustered to support it. However, in some cases, an allegation may be baseless, without any facts to back it up.
In court, an allegation is a formal accusation which will be explored during the course of a trial. In many regions, the burden of proof lies on the party making the allegation, in which case they must demonstrate that the allegation is true while the defense attempts to show that it is not. Both sides may call witnesses and present evidence to support their interpretation of the case, and when the trial ends, the goal is to have presented the case convincingly enough that the judge or jury believes it.
Outside of court, newspapers and other news media are often the most likely to make allegations, asserting factual information on the basis of investigative journalism. Sometimes these allegations later develop into legal cases, as when a television station suggests that someone is breaking the law. In other cases, they are designed to draw attention to community issues which are not getting enough coverage. The actions discussed in the allegation may be technically legal in these cases, but ethically questionable.
The media have to be careful about how an allegation is framed, and about how reporting on people who have been accused of crimes is presented. People may be able to bring suit if they feel that reporting was erroneous or damaged their reputations. For example, when reporting on a murder trial, the media cannot say “the murderer opted not to testify in the case, on advice of the legal team,” and must say instead “the alleged murderer...” to stress that the trial has not yet been completed and the defendant stands only accused, not guilty.
Before making an allegation, people are usually strongly encouraged to gather facts and information to support it. If someone makes repeated baseless allegations, accusations in the future may carry less weight, even if they are actually based in verifiable fact.