Could a teenager charged with a crime claim that he could not possibly receive a fair trial since the jury would not be comprised of his “peers”?
'Fraid not. The peer requirement just means that the jury must be a “body truly representative of the community”, not just any special group or class. You can challenge the striking of a minority juror on the basis of race (what you’re actually doing is exerting that person’s constitutional right to sit on a jury for them), but you can’t protest that the jury composition isn’t close enough to you in age or social standing to constitute a “peer”.
He could not successfully claim that the jury was illegal because it was not a jury of his “peers.”
Many cases have stated that “jury of peers” does not refer to every demographic attribute that a person may have (age, sex, race, occupation, income level). In its day, the term probably meant that a nobleman would be tried by noblemen and that commoners would be judged by commoners, in order to avoid cross-class prejudices. Today, however, the term refers to the fact that the jury will be a group of ordinary citizens who are not governmental actors–the suspicion is that governmental actors (even judges) may uphold the thinking of the government in order to protect themselves politically. This is, aparently, avoided when the jury is a random group of ordinary citizens and they get to decide whether the actions of the defendant are criminal.