The grand jury's job is to determine if there is ENOUGH evidence to warrant a trial - that is all.
They arent to determine the guilt or innocence nor are they to even consider possible length incarceration nor severity of punishment IF guilty.
From what little information is given in the article, this case is reminiscent of a case that occurred in Oregon 4 or 5 years ago where the girl, without the foreknowledge of the boy, had snuck out of her house in the middle of the night, broke into the boys house and had sex with him. The girls parents noticed her gone and having not thought to call the boys parents, assumed she was out partying or something. Logically, the police checked the boyfriends house, discovered the girl and arrested the boy.
Over the objections of everyone involved, including the girls parents, the police held the boy and the DA pressed charges. The boy was sentenced to three or four years of prison.
People on this thread are bound to yell at me for saying it but, the circumstances described in the article hardly call for a slam-dunk prosecution.
The Grand Jury may have been privy to information that indicated pursuing a criminal case against the boy would have been unjust. And while that's not the job of the Grand Jury that is the original and defining premise of the American Legal System: that it is a greater crime to enforce a law which is inherently - or which circumstances render - unjust, than is the original crime itself.