I had to read this story a few times to really believe what I was reading. I refer to this kind of parenting as " lawnmower parenting " mowing over the "real" issue and stripping your child of accountability. Blaming this crime on social media is a deflection on the parent realizing their own child could do something so awful.
He is in grade 12 and should be held accountable and who ever else was involved, for a person to act in this way, there has to be a bigger issue here and hope some where down the line you all figure it out. My first step would be charging the little bugger for pre meditated attempt to disrupt and destroy property with the sole intent to "wreck"
Accountability is a tool we are stripping from our youth, always bailing them out and making excuses for their benefit. As parents we will not always be there and need to prepare them for the real world.
I get you are devastated and I feel for you, take back your power and make your son accountable. He will thank you one day, I promise.
Child and Youth Care Practitioner