There are conditions. One of the conditions is that a 15 year old can not buy a gun. An adult can not purchase a gun for a minor. There is some leeway for hunting equipment used under the guidance of an adult.
This, however, was an automatic pistol. Not a hunting rifle. There’s also responsibility for adults to secure guns safely. There’s no evidence that whoever sold the gun was ever given an indication they acted outside the law or knew the gun was for a minor. Whilst I don’t agree with the guns laws in the US, the people acting illegally were the parents. The gun was sold legally.
Being able to buy a gun doesn’t mean it’s then legal to hand over a gun to a minor. In the Uk, as an adult, I can buy alcohol. I can get in trouble for buying a minor alcohol, especially if that leads to incident where someone is harmed.
Regarding her part in this, she knew he had free access to a gun. She knew when she attended the meeting at school that her son had access to a gun and had been drawing out a school shooting. She also refused to take him home and get him help. She also saw the drawings and declined to tell the school there was a possibility of him carrying a gun.
The school didn’t search his backpack, but that appears to be a grey area of wether they should or could do that.
She did see things coming. Because when she heard there had been shots fired at the school, she text her son and told him not to do it. How many parents would jump to their son being the source of the gunshots, if there’s been no red flags.
She immediately knew it was him. If there was an incident at my son’s school, not a chance would I jump to the conclusion he caused it. My first thought would be concern for his safety.