Why do some police cars have all blue lights and others have red and blue?

You’re asking us?!? ;)

“Police agencies may use red, blue, or both, depending on the state, along with white and amber as optional colors; although amber is usually restricted to face behind the vehicle. Some police cars have an amber traffic-control stick, or “arrow stick”, behind the lightbar to direct traffic left or right around the vehicle; these usually have 6 or 8 rear-facing lights that flash in sequence.
Some privately-operated special police are allowed to display the same colors as regular police, generally, if they receive their special police authority at the state level. This can include railroad, university, hospital, and humane society police departments.”

Wikipedia:Emergency vehicle lighting

You’re fired!lol!

Go easy on me Lucy.

Hm…

around me, the county Sheriff’s vehicles are red-and-blue, the Highway Patrol is all blue, and the city cops…. I think they do red and blue also, maybe with white(?) (I don’t live in the city limits).

The Sheriff’s Office also has a “citizen service unit” (read: Completely unhelpful, useless volunteer retired officers with nothing better to do than waste taxpayer dollars on fuel and auto maintenance) that uses all amber lights.

I wonder if the differences are so they know whether their team has a dog in each fight?

Hi, we have red and blue lights here, for all the departments, only difference is the sound slightly.

@John-That’s what they all say!lol!

@john65pennington I saw this question and figured you would answer it. Quite surprised to see that you asked it. My guess? It’s a matter of preference of whoever is in charge of buying the lights.

To be honest, i already knew the answer before i asked this question. i was hoping the answers would tell me what cities have what color combinations on their police vehicles. this was more of an educational question, than anything else.

@john65pennington I can’t think of the last time I saw all blue lights. Cincinnati has red and blue with amber on the back and there’s enough white in there to occasionally be very annoying when you have to pass someone who’s been pulled over.

Gee my city now has those uber bright low rider light bars that have red, blue and white lights and you don’t want to be within a ¼ mile of that light show!! I think the new setups provide for selective use of the colors too depending on the type of emergency I only assume here.

In NJ, police use combinations of red, white and blue . . . EMS and Fire personnel are allowed to have Blue lights on their private vehicles when responding to an emergency.

In NYC, cruisers use red and white light bars when in pursuit. They also have yellow light bars that rise from a horizontal position to vertical when assisting disabled vehicles. the raised ligt bars help alert oncoming motorist to the road block/hazard ahead.

Driving down I-95, I have noticed that MD, VA, NC & SC state troopers have blue& white lights

It depends… laws very from state to state. Primarily on the east coast you will see more agencies with all blue lights, while the west coast more likely has all red. The midwest is most prevelant for both. This goes back to the early days of law enforcement, the two coasts each had there own development of law enforcement practices. As the midwest grew slower they were able to adapt the best of both coasts. Most areas now are switching to a combination for safety reason, being easier to see multi-colors especially at night. However, such as in the state of Florida state law says “police” may have red and blue lights where as blue is authorized to sheriff’s deparments. Therefore depending on how strictly the law is interpretted most city police departments will have red and blue, but most county sheriff’s will only have blue. So long story short… it depends.