It is because he isn't an "official" government agent. Only "official" government agents are authorized to fight fires.
I am glad that I don’t work there. Around here the police assist homeowners with anything that they have got to help keep fires under control until we arrive. They worry us because they often run into burning rooms with extinguishers or garden hoses and no protective clothing. The police that I work with are determined to protect people and property. I have been to dozens of incidents where the police and/or residents have put out or kept fires from spreading using garden hoses. I thought that I worked in a screwed up liberal part of the country... but at least a little common sense still prevails around here.