IMPOTENCE (Lat. impotentia, want of power), the term used in law for the inability of a husband or wife to have marital intercourse. In English matrimonial law if impotence exists in either of the parties to a marriage at the time of its solemnization the marriage is voidable ab initio. A suit for nullity on the ground of impotence can only be brought by the party who suffers the injury. Third persons—however great their interest—cannot sue for a decree on this ground, nor can a marriage be impeached after the death of one of the parties. The old rule of the ecclesiastical courts was to require a triennial cohabitation between the parties prior to the institution of the suit, but this has been practically abrogated (G. v. G., 1871, L.R. 2 P.C.D. 287). In suits for nullity on the ground of impotence, medical evidence as to the condition of the parties is necessary and a commission of two medical inspectors is usually appointed by the registrar of the court for the purpose of examining the parties; such cases are heard in camera. In the United States impotence is a ground for nullity in most states. In Germany it is recognized as a ground for annulment, but not so in France.