The
adversarial system or
adversary system is a legal system used in the
common law countries where two advocates represent their parties' positions before an impartial person or group of people, usually a
jury or
judge, who attempt to determine the truth of the case. It is in contrast to the
inquisitorial system used in some
civil law systems (i.e. those deriving from
Roman law or the
Napoleonic code) where a judge or group of judges investigates the case.