Well:

A) That's a shitty way to debate

B) If you are looking for a perfect study to fix the exact question you are looking for then sorry bud, you ain't gonna find it. Science doesn't work like Rule 34. You essentially build the house of your argument out of the information you have available. In this case, we can get pretty close to your questions at hand, but alas, it isn't quite possible to fit it perfectly. Like, the block fits in the hole, but there is a bit of wiggle room. It provides us a reasonable assumption regarding your question and I see no reason why that shouldn't be considered good enough here. 

Well you gonna have to be very precise and questions directly answered if you gonna persuade people to give up perceived basic rights.

So you're just planning on endlessly stonewalling while kids die because your hyper-specific questions don't have perfect answers?

Cool.

Cool.

When do we start to acknowledge the basic rights of our kids to not get fucking murdered in their schools?

What?

How are gonna make change you want if you can't persuade people?

The kids getting slaughtered in their schools should persuade you enough, honestly. 

Besides, the data we have is pretty good. It is simply unreasonable (and vile) to demand all your questions be answered perfectly by limited data on mass school shootings before being willing to act. 

Its not me you hv to persuade

Nvm, no more feeding the troll.

The parents of the victims need to sue the city, the school, the police department, the county and the state for the slow response time. That way at least something will chance eventually on a local or state-wide level.

Collect data, decide if it helped and if it should stay law. 

Also known as problem solving.

I look at my parents generation and wonder what the fuck where they thinking with racial discrimination, never understanding how it took so long for civil rights legislation.

I feel like my kids are going to think the same thing about gun laws when they are older.