Please Explain

This past week, a mass-murder happened in New Zealand. As it so happens, New Zealand has gun control laws somewhere between the levels of Australia and the United States. But these laws did not stop the horrific murder of 49 people.

I have to ask this question, and thus far, no one that is in favor of banning firearms has been able to definitively answer it…

How exactly does restricting or banning firearms from lawful citizens fight crime or reduce gun-related violence?

I’m waiting…