April 4, 2007 - I feel that some sort of warning light is a good piece of standby equipment for a chase vehicle, and can be of good use for public safety in rare situations. They should be used with extreme judiciousness and only when absolutely neccessary. I have strobes installed on my vehicle, and own a small lightbar that is usually not installed. I've had this equipment since 2003 and have used it maybe once or twice per season while chasing, usually for no more than a minute at a time. Examples include blocking traffic from a flooded roadway at night, alerting traffic of icy bridges, warning traffic of debris or trees across a road, or alerting traffic behind me that I am about to turn onto a pull-off on a narrow road. I have used my lights many times in the presence of city and state police at icy road accident and flooding scenes, and none have raised any issue with me about it. In several cases, I've been *thanked* by law inforcement for doing the above actions until they were able to arrive. But, most of these scenarios are unique and rarely involve tornado chasing.
Reading the laws across the country, it is easy to see that in most states, it's not the lights that are illegal but how they are used. With a few exceptions (California and Illinois are two of them), amber lights are allowed to be used to supplement a car's four-way hazard lights. They don't give any right-of-way, authority or permission to speed or park illegally, just like four-way hazards do not.
The problem I see that is the main 'beef' with everyone, and the source that triggers these discussions, is with running the lights during one's entire 'intercept mode', which I think is a phenomenon mostly derived from movies like 'Twister'. It's like once you're in 'intercept mode', you kick up the action/drama and get excited, turn on the lights and close in on the tornado. Although the intentions here are understandable and harmless, the implications are not. In most states, doing this is illegal.