Peremptory plea
（重定向自Autrefois convict）
In the common law, the peremptory pleas (pleas in bar) are pleas that set out special reasons for which a trial cannot go ahead. They are the plea of autrefois convict, the plea of autrefois acquit, and the plea of pardon.
A plea of autrefois convict (Law French for "previously convicted") is one in which the defendant claims to have been previously convicted of the same offence and that he or she therefore cannot be tried for it again. A plea of autrefois convict can be combined with a plea of not guilty.