Summary execution

A summary execution is when a person is accused of a crime, and killed immediately, without a full and fair trial. Very often, summary executions happen in wartime. Under international law, a person is able to surrender. People who have surrendered may not be killed using summary execution. Killing a person who has surrendered is also seen as summary execution, and usually treated like murder and a war crime.
Civilian jurisdiction.
In nearly all civilian jurisdictions, summary execution is illegal, as it violates the right of the accused to a fair trial. Almost all constitutions or legal systems based on common law have prohibited execution without the decision and sentence of a competent judge, and the UN's International Covenant on Civil and Political Rights (ICCPR) has declared the same:
In practice, though, extrajudicial killings have been performed by police and domestic forces in various countries and times, sometimes under martial law. It is also performed by armed bands fighting against governments and common citizens.