The report I read earlier today said that all the guns had been bought legally. So let's see:
- Columbine: Guns bought legally. Stolen from parents by shooters. Check.
- Sandy Hook: Guns bought legally, shooter killed mother to get guns. Check.
- Fort Hood #1: Guns bought legally. Check.
- Virginia Tech: Guns bought legally. Check.
- Boston marathon: Pressure cookers bought legally. Check.
- Aurora Theater: Guns bought legally. Check.
- Navy Yard: Not sure -- was his gun bought legally?
- Fort Hood #2: Gun bought legally. Check.
- San Bernardino. Guns bought legally. Check.
The other thing I'm curious about is that they are reporting at least 75 rounds fired. CA has a ten round mag limit, and I'm pretty sure both models of AR used have the cosmetic features that require a bullet button, which for those not familiar, requires the tip of a bullet or a tool to be inserted into an indent to release the mag. There are going to be no rapid mag swaps with that. If they did swap mags (legally) they slowly swapped to another ten rounder.
While there are plenty of pre-ban standard capacity mags floating around, given the killers ages, I don't believe there's any way they would be in legal possession of such. If they bought their guns legally, they would have ten round mags and most likely bullet buttons on the rifles. If they showed up with rifles, it doesn't seem logical that they would empty ten rounds, then switch to pistols for the rest of their attack. My bet would be some lawbreaking occurred regarding weapons and mags, which would show the ineffectiveness of CA laws.