If it were an official way to train dogs then it would be a nationwide scandal. However, the handlers can always train them in their own time. After all, besides a K9 being a partner, they also live with their handlers. I wouldn't be surprised if some handlers have done just that - to alert on a subtle (subtle enough) physical queue or even command, like "Search buddy" instead of "search go."
I know a guy who is a K9 handler for the police force. He runs a security camera company and uses his customers footage to track people in police chances and such. He also was given a restaurant and a manufacturing plant that produced masks during covid. Dude did security cameras for a company I worked at and pulled out his police officer pistol to show it off just like about everything else my comment mentions. I don't think he should have a gun or a police trained K9, but maybe that's what qualifies him...
When I was in highschool, I got dragged out of the back seat of a car with 5 of my friends, laid face down on the asphalt inches from the lane marker, and they proceeded to rip out EVERYTHING from my friend's mother's minivan. When they started pulling people, oen friend sent an SOS text to his parents.
When they found nothing because the only illegal thing anyone was planning to do was underage drinking like 6 hours from then, they proceeded to LITERALLY begin ripping the car to shreds. Broken plastic panels "these are easy to remove, they could be hiding shit in there" and ripped upholstery "that loose seam means they hid it in the seats" and even began removing the bumper.
Then the friends dad, who at the time was a legal aid, now lawyer, pulled up and began theCALMEST dressing-down I've ever seen from someone who is seething with rage.
Popped up, got out of the car with his hands out to the side, immediately identified himself as "their legal representative" and began reciting all the laws the cops were breaking, since they never had probable cause to begin with beyond "hey there's teens in that car" (he had no way of knowing that, for all he knew we got pulled over for legitimate reasons) but he trusted his son.
I'm sure we would all like to pretend they got fired, but nah. They took off the cuffs, said something along the lines of "don't give us a reason to stop you" which sounded an awful lot like a threat to me, and nothing ever came of any complaints.
You were blessed to have your friends dad show up. Sometimes they do weird shit like grab your wrist so when you pull away they can get you for resisting and they beat your ass after situations like that.
Oh yeah, I'm 100% glad he got there when he did, it was January and literally freezing, and I'm sure they would have done something to get the excuse they were waiting for.
If you or someone you care about has the SOS feature on their phone (specifically the one that you can specify NOT to call the cops for) then have them set it up to get ahold of someone they trust.
My wife's phone is set so when she mashes the power button a bunch, it automatically sends me and her best friend a text with a customized message, in this case just "SOS I NEED HELP ASAP SOS" her approximate location based on cell towers and if her fitness watch is on or phone GPS is active, her GPS coordinates and a link to follow the signal.
She watches a lot of crime docs, so got paranoid about being kidnapped or in a situation she can't take out her phone without an excuse. So all she needs to do is be able to press the side button repeatedly.
Yeah I got pulled over once and illegally searched by dogs. They supposedly alerted. It totally wasn't that half a Subway sandwich on my passenger seat. They proceeded to tear my car apart anyway while simultaneously trying to convince me to confess to drugs that weren't in my car. Scumbags.