Why do police cars sometimes have their lights flashing but the siren is off?

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Why do police cars sometimes have their lights flashing but the siren is off?

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6 Answers

Anonymous 0 Comments

It’s a sliding scale of urgency. With the lightbar on but sirens off, an emergency vehicle can still be visible and slow traffic around them, but without the extra emphasis of, and attention attracted by, the sirens. I’d imagine an officer might do this when in a quiet residential area or when responding to a minor incident (e.g. fender bender, no injuries), or when they want to respond rapidly to criminal activity without tipping off the perps that they’re nearby.

Obligatory disclaimer: I’m not a police officer. I *am* an EMT and drive an ambulance; while I can’t claim to speak for officers and therefore I can’t claim my answer is accurate, I can tell you there’s a few situations in which *I’d* run lights-only, and conceptually my answer is based on that.

Anonymous 0 Comments

let’s say I buy drugs with cryptocurrency on TOR browser. The drugs will arrive to my address. But aren’t all the packages controlled by the customs personnel on the border or by the post office personnel before they deliver them? In that case I’ll be caught, how is that safe?

Anonymous 0 Comments

They do this at some times when it is late at night and they don’t want to wake up people by running their sirens. Other times, it’s that they are going “I need to get the right of way, but it’s not a SUPER emergency.”

Anonymous 0 Comments

They may not want to advertise themselves before they arrive on scene. Ever see a heist movie where the robbers hear sirens and decide it’s time to leave?

Anonymous 0 Comments

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Anonymous 0 Comments

Lots of reasons… Mostly because it’s unnecessary and disruptive in some cases. If traffic is already moving favorably, the siren can cause more issues than it solves. You learn how drivers react to different things and adjust accordingly. On the fire engines we have another option too with the growler that you can basically set at a certain level and let it spin which can be helpful for alerting pedestrians or cyclists or other cases where you don’t want the full siren. It’s a big part driver’s preference too… I’m personally on the less siren is better side; some guys leave it on the entire time. For me if I need you to move or I’m concerned about alerting at an intersection or blind turn, it’s on. Otherwise, and almost always at night, it’s off.

Source: drive fire engines.