Everything listed so far in the thread is very good, and I think that communications should be mentioned. Communications is truly essential these days for law enforcement officers, and there isn't enough of redundancy for my liking, so here are some things:

1) As an emergency services worker, you should be more familiar with communications systems than the average person. You don't really need to know theory, just how things are connected, and perhaps how things might fail.

2) Check to make sure that your cell phone providers are not sharing towers/equipment. It is possible that both are leasing tower space from a third party, or from one another. If you are in law enforcement, you should be able to have your Homeland Security Coordinator/liason find out this for you. You don't need to know specifics, just that they're seperate.

3) I would also consider either:
A) Getting an amateur radio license, and having a radio in your cruiser, or on your person. They're cheap, and most come with battery packs for AA/AAA batteries. Car units aren't too bad in price either. If you get a General license, you can get HF, and can go farther. This all depends on who you want to communicate with.

B) Getting an older VHF/UHF (dual-bands if possible). Program it with frequencies that would be monitored by someone (i.e. MED channels, Nationwide Law Enforcement, State Police Shared/Common, State Fire Shared/Common, etc.). Could be useful where an 800Mhz TRS system is. Make sure that your 800Mhz radios have the Nationwide 800Mhz TAC channels in them (there are 5 plus 1 calling channel). For the VHF/UHF frequencies, amateur radio operators may be able to (no guarantee) transmit on the frequencies listed above, under FCC Part 97 (Amateur Radio), 97.403 - "No provision of these rules prevents the use by an amateur station of any means of radiocommunication at its disposal to provide essential communication needs in connection with the immediate safety of human life and immediate protection of property when normal communication systems are not available." If you are trying to reach someone, and you don't get anyone, and its an emergency, try calling specifically for an amateur station. Amateurs like to follow the law, and its nice to have clear cut words that let us do things. <img src="/images/graemlins/smile.gif" alt="" /> I'm really not sure of the consequences, but I'd be comfortable responding to you if no one else had.

C) Both. The more you get, the more logistics required for power (different battery requirements, etc). If you don't want to trouble yourself, contact a local amateur radio club, and they'll find someone to consult with you to get something that you can manage.

In the long run, smoke signals work just fine. At least the fire department will show up! <img src="/images/graemlins/wink.gif" alt="" />