> A law like this clarifies exactly where that line is expected to be.

It sets a specific measurement, but it would be extremely difficult to prove someone was or wasn't within the set distance.

The court will always defer to police over other witnesses.

The law is completely unnecessary for the stated purpose. Every state already has plenty of "interfering with a police officer" type laws...and there's no epidemic of people filming stuff, getting in the way of police.

This law is a softball for the supreme court to use to revoke their prior ruling that filming police is constitutional.

I suspect it's also designed to stop passengers in a stopped motor vehicle from filming - a few police shooting cases involved footage taken by a front seat passenger, showing the driver never made any threatening moves.