Police do not. Homeland security convinced every agency that "common language" should be used instead of signals and ten codes. But truckers certainly do.

I will add, as former LEO that in my opinion, NSA / Homeland Security wanted us all to use common language so if we were using 10 / signal codes behind their backs they wouldn't be able to decipher every single city/county/state's codes if there was a "disaster"... Now what you have is every new police recruit and dispatcher everywhere is not being taught the old codes. They say "traffic stop" instead of Signal 27 or Driver's License Check instead of 10-27.

Police do not. Homeland security convinced every agency that "common language" should be used instead of signals and ten codes. But truckers certainly do.