Petit Jury (or Trial Jury)
A group of citizens who hear the evidence presented by both sides at trial and determine the facts in dispute. Federal criminal juries consist of 12 persons. Federal civil juries consist of at least six persons.
Source: U.S. Courts
A group of citizens that listen to the evidence presented by both sides at trial and figure out the facts in dispute. Criminal juries are made up of 12 people; civil juries are made up of at least 6 people. (See also jury and grand jury.)
Source: California Courts.