These move-over laws simply shift the danger from the guy on the side of the road to everyone else. This is another one of those typical 'feel-good' laws that do nothing to fix the problem they're designed to resolve - and simply make things worse.
Does anyone think for a moment that anyone deliberately smashes their vehicle into emergency vehicles? Short of a suicidal nutbag, that just doesn't happen. It's careless, inattentive, distracted, sleepy, or incapacitated drivers that do. So, how does a move-over law get any of those people to suddenly care more, be more attentive, less distracted, more awake, or less drunk? Simple. It doesn't.
What it does do, however, is cause law-abiding, attentive, and alert drivers to make abrupt changes from normal driving. That means other, less attentive drivers caught in a middle lane, for example, who can't see past the 18-wheeler in the right lane are caught off guard when without warning that 18-wheeler tries to force his way over. In extreme cases, much like rubbernecking, the whole mass of cars will slow suddenly to make room for one another - creating accidents.
It's a well-intentioned law, but it does nothing to stop the underlying cause.
It reminds me of the no-texting laws that have gone mainstream. No one wants anyone to text. So there is little opposition to the law. Yet, all it has done is taken an admittedly dangerous practice of texting in the open (with the phone held up and over the steering wheel where the driver still has use of peripheral vision), and made it exponentially more dangers. Now those same drivers who will text no matter what law is passed, will do so with the phone in their laps (to conceal the illegal activity). Now they have no peripheral vision, and are MUCH more likely to get into an accident.
I don't know what the solution is, but this is not it.