A recurrent issue in juvenile proceedings is whether the subject of an investigation was under the age of 18 at the time of the offense and whether he or she now is under 21 for the purpose of juvenile delinquency proceedings. See 18 U.S.C. § 5031.
If you have a question concerning the subject's age and the subject has no undisputed proof of birth date to offer the court, we have taken the position that the burden of proof is on the person claiming the benefit of the federal juvenile statutory provisions, especially since that person is in the best position to offer evidence of his or her age. On the other hand, if the exact date of the offense is the critical issue, that burden will probably be placed on the prosecutor.
From the outset of an investigation, there is a need to exercise certain precautions when proceeding against a juvenile. Some examples follow:
[cited in Criminal Resource Manual 48]