A tow truck is an emergency response vehcile for accident scenes and any police scene it is at. A tow truck is not classed as an emergency vehicle in the UK.
Where I live (Alberta Canada) a tow truck is considered a highway maintenance vehicle.This means for the purposes of the time it is working on the highway traffic must treat it the same as a police...
all vehicles can be towed,as far as automatic transmission ,short distances in neutral is usually ok ,longer distances some recomend disconnecting the drive shaft ,all in all most towing companies...