An offer of recompense given by authority of law for the performance of some act for the public good; which, when the act has been performed, is to be paid; or it is the recompense actually paid.A reward may be offered by the government or by a private person. In criminal prosecutions, a person may be a competent witness although he expects, on conviction of the prisoner, to receive a reward.
By the common law, informers, who are entitled under penal statutes to part of the penalty, are not in general competent witnesses. But when a stat-ute can receive no execution, unless a party interested be a witness, then it seems proper to admit him, for the statute must not be rendered ineffectual for want of proof. Gilb. 114. In many acts of the legislature there is a provision that the informer shall be a witness, notwithstanding the reward.