I don't think it would be a mistake to say any time he used his siren would be abuse.
Let's be candid: These high and mighties had these sirens simply because they could. Not sitting in traffic like the 'little people' is one of the perks that comes with being one of the annointed. I find northeast governments rife with this attitude. In fact, I strongly believe such perks are what motivates many 'public servants' to begin with.
Take away these little emporers license to do whatever they like and maybe, just maybe the people left who want the posiition might have a more humble mindset and actually do some good, or at least less damage.
More than likely, the equipment has been standard issue on all the vehicles for years, and isn't assigned because of any particular position you hold. This could have been standard practice through several administrations.