I would suggest that there are many possible outcomes for your son, including several that would provide a pretty fair result for him.
There are several reasons I state this; he has no criminal
history, the offense is not terribly serious and the mushrooms were purchased in a way that implies a non-criminal activity.
Some type of a diversion program may be appropriate. Every jurisdiction is different, but many jurisdictions offer a diversionary program for people with little to no criminal history. Such a program would likely involve drug counseling, drug tests and perhaps community service or some other such "punishment". If your son successfully completes the program, all charges are dismissed.
As you suggested, a reduction to some type of misdemeanor
offense seems quite possible. Again, with little to no criminal history, a prosecutor certainly may be willing to do less "harm" to your son and prevent him from entering a plea to a felony offense.
Worst case scenario, a plea to the charged offense with some length of probation, perhaps 18 to 36 months, seems quite possible.
As this is a criminal case, and it could effect your son for sometime to come, I would urge you to check into retaining a criminal defense attorney in your area. Such an attorney could do a great deal towards protecting your son's rights.
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