According to the traffic rules, only one red-blue flashing light, devoid of “sound”, does not give traffic police personnel any advantage on the road. But the cops don’t seem to care. There could be several explanations for this.
First, they simply forgot to turn off the “chandelier”. Something glitters on the roof – and God bless him, does not interfere with life. The second version has a more meaningful “base”. The fact is that most car owners do not really remember the rules for passing special vehicles and, just in case, are ready to give way to a car with a “flashing light”, even in complete silence.
It is useful for law enforcement. You do not need to re-tighten and steer – other cars themselves give way to the “owners of the track”. Driving with a special light signal, but without a siren turned on, is practiced by the traffic police, even in the event that the crew really rushes with an urgent matter.
The “trick” here is that not all rulers of the striped wand like the siren continuously yell above their heads. To spare their eardrums, they don’t turn it on, they just fly forward. And only when they “rest” against the back of the car of an ordinary car owner, do they supplement the already working “flashing lights” with the supply of short croaking sounds from their car’s speaker.