About a decade ago, "magic wand" bomb detectors and similar products were pretty big among security services in places like Iraq. [1] Their various supposed methods of operation were transparent BS, in ways that make the EM drive proponents look rigorous.
What always struck me about reporting on them was how there was a great deal of coverage about how fraudulent they were, but seeming puzzlement on why security services would keep buying such obvious BS. What seemed clear to me, was that the BS was the point. Similar to polygraphs and drug-sniffing dogs, the purpose of the tool is to give the investigator a seemingly-objective excuse to follow their intuition (or engage in arbitrary targeting and abuse; take your pick).
I was once in an airport in some third world country and one of those dogs was pointed at my luggage. I was really worried their operator would give them some secret signal to find "drugs" in my luggage. Nothing happened but I can imagine that's a thing.
Those wands were completely fake. Dogs do have a keen sense of smell and can be trained to sniff certain substances.
The polygraph I think is more in the disputed category. It actually measures some physiological signals which in theory could correlate to stress.
That said I don't disagree. These tools can be abused. At the end of the day you need various checks and balances in all these systems (e.g. FBI's internal investigation or whatever body is involved in the security clearances in the US in this example). Applying psychological pressure in various ways is a legitimate tool in these domains.
What always struck me about reporting on them was how there was a great deal of coverage about how fraudulent they were, but seeming puzzlement on why security services would keep buying such obvious BS. What seemed clear to me, was that the BS was the point. Similar to polygraphs and drug-sniffing dogs, the purpose of the tool is to give the investigator a seemingly-objective excuse to follow their intuition (or engage in arbitrary targeting and abuse; take your pick).
1. https://en.wikipedia.org/wiki/ADE_651