My name is ***** ***** I'd be happy to answer your questions today. I'm sorry to hear that this happened.
There are two separate issues here - one is the criminal
charge for assault, and the other is the fact that he was on probation when this happened. To prove assault, the government needs to establish beyond a reasonable doubt that your son spit on this girl. That's going to require a witness to what happened. The police officer cannot testify as to what the girl told him, because that's hearsay. His friend could testify that he was there and as to what happened, and so could your son, if he chose. But assuming she didn't go to the hospital (and why would she), unless your son admitted to spitting on the girl, there's no evidence.
A person who fails to appear after receiving a subpoena is in contempt of court. She could face criminal penalties for ignoring the subpoena (if they send one - they may not if they don't realize she doesn't intend to appear).
If your son is found guilty, then he will also be charged with a probation violation. If he accepts a plea, that's ALSO a probation violation, so he needs to be aware of that - it's usually a good idea to take the case to trial if you're charged with something while on probation.
The standard of proof in a probation violation is lower than criminal court. So it IS possible that they'll hold a violation hearing even if he's found not guilty on the charges. That's something to be aware of. But at the hearing, again, they need some evidence that your son spit on the girl. That means the state needs a witness. Again, they can subpoena her. If she fails to appear for the criminal hearing, they're more likely to subpoena her for the violation hearing.
If your son had a lawyer for whatever he's on probation for, it's a good idea to call and talk to that person. If not, he may want to consider hiring a local attorney to help both with the assault charges and the likely probation violation that could arise. Sometimes, too, it can help to talk to the probation officer. If that person is on your son's side, it can go a long way in the hearing, because the judge will often accept the officer's recommendations regarding whether punishment is needed.
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