I don't see how you can claim the burden falls on him. They already presented a study saying how many assaults happen on cops per year, if you want to refute th

I don't see how you can claim the burden falls on him. They already presented a study saying how many assaults happen on cops per year, if you want to refute that study with evidence then that's your burden - It's not their job to form your arguments for you just because you think you're right.