As a parent and gun owner I'll preface this by saying I have both a minor at home AND loaded guns.
I have trained my child in the use of firearms as well as acceptable use of said weapons (home invasion).
With that being said, what if my child decided to do what this kid did today?
Am I responsible?

Too many 'depends' to give a good answer

I'll narrow the "depends".
My child knows where one of the loaded weapons is located.
(Wouldn't do any good in a home invasion scenario to have to spend valuable time opening a safe).

In this kind of hypothetical, I would ask questions like:

Is it negligent for a parent to have firearms stored in the home without being secured by a lock, safe, cable, or other device?

Is it negligent for a parent to leave a firearm within easy access to the child?

Did the parent negligently leave the firearm accessible to the child?

The answer is NO

That�s a great question right there... sad thing, back when I was in high school (late 80�s), it was normal to see a students truck in the parking lot with a shotgun rack with a shotgun in it. Most of us hunted birds after school. If you did that nowadays, you would be kicked out of school and sent to prison. Different day different age...
what happened to us as a society?

And this piece of [censored] was 17 and an adult in the state of Texas.

I think if a parent can show they have done all they can to teach and train a child in the proper use of firearms and stores firearms properly, it would be hard from me to blame the parent. The child was shown the right path and purposefully chose not to take it.

I guess the big question in all of this is where you set the line for parental effort vs. willful negligence.

It is a tough hypothetical with many "what ifs".

I dont want a child with hormones running wild quick access to a weapon. I will take my chances with home invasion but Im not going to take a chance
my kid does something stupid on accident or otherwise, chances are a hundred times more likely than repelling an intruder.

Yeah, my inclinations run the same way. I'm willing to use a biometric pistol safe by my bedside to ensure that I'm not leaving a loaded gun where a kid can grab it.

On the other hand, what is a "reasonable" method of securing guns? Is a locked gun cabinet with a glass door enough to be a barrier to your kids? Do the guns in the cabinet need a cable lock run through the trigger guards (or magazine wells)?

Depending on your children's tendencies, I don't think it should be necessary to have every gun stored in an armored safe, just secured by reasonable means. On the other hand, if you think that your kid is such a high risk that you have to use a super-duty gun safe, that could be a sign that something is fundamentally wrong with the kid and might need to be in a hospital setting or such.

That�s a great question right there... sad thing, back when I was in high school (late 80�s), it was normal to see a students truck in the parking lot with a shotgun rack with a shotgun in it. Most of us hunted birds after school. If you did that nowadays, you would be kicked out of school and sent to prison. Different day different age...
what happened to us as a society? [/quote

When I was kid I had my own shotgun (unloaded) stored in my closet. Mom and Dad had !oaded pistols in their bedroom. My brother carried a pistol in his car from the time he was old enough to drive. Cant do that today. We never thought much about it. We grew up wirh guns.

I was taught at an early age that you "don't shoot anything you don't want to kill " . After the correction I received upon shooting my Dad's rooster and my brother with my first Daysi , I took that lesson to heart .

Sorry to sound like an old but kids today are being raised by their electronic devices ( video games , etc. ) and have no realization of the suffering their actions can cause .

You think that's what happens? Hormones? Kid wakes up and suddenly the hormones make them kill?

The wheels are off these kids long before they kill. Over and over the signs were ignored. That's one consistent fact in these mass murders.

Most of us here agree that more government is never the best solution. Myself included.

However, in the case of the murder of children, at what should be a place of growth, joy and learning, I could support some tweaks to existing laws.

LE needs the teeth to follow-up on all "these leads, media, contacts and corroborative information." School administrators must report all suspicious situations without fear of reprisal. Financially or otherwise.

Once that criteria is met, the process of evaluating the student and their family begins immediately. Anyone deemed a threat goes to a mental health facility. For a minimum of 72 hours, up to 148 hours. Their stay may be extended indefinitely based upon further evaluations, observations and recommendations of facility senior staff + the courts.

Sound reasonable? Didn't think so. 'Specially after I took away all your freedoms, indefinitely.

Imagine twice the population in America to what it is now.