Can polygraph tests weed out bad cops?

Originally published at: Can polygraph tests weed out bad cops? | Boing Boing


In other words, polygraphs can have a placebo effect on assholes.
Now that 's kinda neat.


ACAB, so every cop is “a bad one”. No need for some quasi-mystical techo-bullshyte.

I also am vehemently opposed to the use of polygraphs in any circumstances.


Michael Cox most recently was Ann Arbor’s police chief. Residents demand PD to engage in “community” policing rather than “broken windows”, which results in a rather non-shooty PD. I think he did fine here and hope he is able to effect changes that are long overdue for Boston.


More rigorous screening might have the same effect. And since we’re going for placebo, dowsing rods that detect assholes might be more affordable.



If this takes off, what’s going to end up happening is a lot of angry young white conservative men are going to all end up taking classes on how to beat polygraph tests. It’ll be right there next to shooting lessons and courses on “pick-up artistry”.

On the one hand, a 75% reduction in violent assholes is a good thing. On the other, polygraphs are a cheap psychological trick and you shouldn’t rely on them.


I guess that would be more a nocebo effect, which is interesting, but I’m with @SpeedRacer in their previous comment - polygraphs are dangerous bullshit that I’m sure have contributed to many wrongful convictions.


Once more, loudly for the cheap seats,


They tell you nothing of value, they are based on garbage, and the sooner they land in the dustbin of bad ideas (next to phrenology and creationism) the better off we’ll all be.


Yeah I suspect they would have seen the same results here if they’d just asked the questions without the polygraphs. Authoritarian bullies tend to not be shy about being authoritarian bullies. Especially those that apply to be cops.


Polygraph tests are default in police hiring.

So are psychological evaluations.

While it’s possible this guy told the people doing the hiring to look out for and eliminate authoritarian tendencies. That’s kinda something that psych eval is already supposed to look for. There’s no magic bullet here.

More over. Applicants who raise flags in the psych evaluation are often told they failed the polygraph. Usually over a minor point such as marijuana use. A little fiction that helps them preserve their reputation, and makes it easier for them to apply at other departments.

To my memory Ithaca was one of those “other” departments for failed wanna be cops in the NYC metro.

Nah but they’re a hell of a psychological pressure tactic.

But applicants to police departments are often carefully coached for the Psych evaluation and polygraph. This tends to happen towards the end of the hiring process, an applicant will already have had multiple interviews, worked with a recruiter, had contact with the Union. If they have any pre-existing relationships with people in law enforcement, which is common, there tends to be a lot more coaching.

So obvious authoritarian tendencies or not. Everyone is telling them exactly how to hide that, or present it as something positive.


That’s interesting, I live reasonably close to Ithaca and have not heard that. Ithaca is over 200 miles away from NYC, a 4-5 hour drive, I’d imagine its not a first stop destination for people who currently live in the NYC metro area and failed to get their chosen career there…
Ithaca is a bit of an anomaly in non-NYC New York. Its a small city (30K population) that doubles when college is in session as Cornell is there, and where most of this central/upstate/western NY area is closer to the south in terms of politics and demographics outside of the city bubbles, Tompkins county where Ithaca is shows up as a glowing neon-blue dot in all election maps. Its a bit of a hippie-crunchy-granola haven and runs far more liberal than its surroundings. Its police have always been a sore spot for their reputation from my slightly at a distance interpretation of them.


I spend some reading the reddits where law enforcement officers and recruits talk amongst themselves, and it does seem like polygraphs are widespread in police hiring. Recruits do seem to have a fear of getting tripped up by them.

I did a deep dive into polygraph reliability when a friend was screwed over by a poorly administered polygraph. My takeaway is that they can be done in a way that gives statistically useful results. Basically you can only ask one (or at most 2-3) simple questions in a session, the question needs to be known beforehand, and they repeat the question enough to get over the noise in the system.

But most polygraphs are not done this way and are unreliable. They are generally misused to get people to reveal information they wouldn’t otherwise, or they ask so many questions that it’s statistically likely someone will falsely fail at least one.


Complete bullshit - on the level of phrenology - but they still use them in one of the largest US funders-of-science, the Department of Energy. While you don’t need to pass one to obtain a “Q” (Top Secret//Restricted Data) clearance or even SCI tickets, I do know that if you get weapons Use Control related access you’re in the poly pool. Strange that in 26y, including even “owning” all of the use control information and related access at my facility I’ve never had one. My wife, not nearly as deep in that world has had four in 20y, some very adversarial to the point that she might just walk if it comes up again.

To my knowledge, a poly has never “found” a spy. What it does however is strike the fear of god into people and they’ll fess up to all of their sins ahead of time.

Nonetheless, it seems like cops are like managers. If someone really, really wants to be one they’re already suspect…

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Lie Detectors; coming from the same brand of woodoscience as James McCormick’s fake bomb detector. Of course, with Cops, you are always going to detect a liar.


Give them Voight-Kampff Tests.


polygraph tests definitely will not repair badly designed institutions


Definitely. Any cop who thinks polygraphs are a useful tool for anything are Bad Cops™.

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I’m well familiar with Ithaca.

You might not necessarily hear the ins and outs of police recruitment if you’re not familiar with it directly. And I don’t think Ithaca would have that reputation in Ithaca. Almost all of the desirable places for those who don’t qualify in the big departments down state are well upstate or northern Jersey, some down in the Carolinas. Mostly in smaller towns, often college towns or small cities.

Law enforcement jobs are mostly civil service jobs. You take a specific police test, usually more than one. Big departments like the NYPD tend to have their own test. But for the most part there’s a state and a county test.

Many departments will hire off the state, or even NYPD test.

While you can apply for a particular position if one is open. Mostly what happens is you are recruited based test scores, and that’s often the plan B for someone looking for a particular department.

The big departments in Westchester, NYC, Nassau and Suffolk County always have plenty of applicants. And so have pretty high standards. You need a good test score and the process is fairly stringent as goes background checks and interviews.

Smaller departments in the NYC subburbs are often pretty desirable too. They tend to pay a lot more in the affluent areas, and can be pretty low key. But they tend to require a lower score on tests than the bigger departments. Because they have to compete.

For anyone who doesn’t score well enough. Or washes out on the application for these jobs.

You wait for an offer from elsewhere.

Being willing to move, or even expecting to is part of the process here.

Ithaca to my memory was always pretty desirable for those who didn’t qualify or washed out. I know more than one jackass who ended up driving a squad car in Ithaca after “failing the polygraph” or because of a “traffic ticket”.

It’s a bigger department. College towns seem less threatening. But it’s small and out of the way. They’re usually hiring, will resort to the state test. And don’t always require the best test scores. It’s not as easy to get into as tiny little departments in small, never heard of it towns. But it pays better and has a full career path.

These excuses aren’t just face saving either, they get put on paper, specifically to maximize the ability of that guy who wasn’t fit to be a cop. Finding a cop job somewhere.

Well a century of research trying to check that has come up bubkiss.

All they do is monitor and graph multiple physiological responses.

In specific with “lie detector” use they’re looking for a stress response.

And properly set up and administered they can reliably detect a stress response in a normal person.

But there is absolutely no objective way to establish why that person is experiencing a stress response.

Maybe they’re holding in a fart. Maybe they’re lying. Many people do not experience a stress response when lying.

Law enforcement use of polygraphs, properly done. Has nothing to do with if they practically work.

It’s a psychological pressure tactic.

People think they work so they can be used as elaborate set piece to pressure people.

You ask questions you already know the answer to.
Point at the machine and say it’s proof you’re lying. And use that pressure to get them to elaborate.

It’s similar on the interview thing. They’re asking things that they already know the answer to, they already know if you lied or not.

The point is to see if you try. And how you respond to the pressure. It’s basically part of the psych exam.


From @thomdunn’s original post:


My only real interactions with Ithaca police were: shortly after we moved there, we were watching a movie at home, and left the door of our one-floor home open, because it was hot, and we liked the fresh air. This was shortly after college move-in time. So then around 11:30pm on a Saturday night, the cops yelled that they were at the door and we needed to come out. They … apparently wanted to make sure there wasn’t a break-in? They were surprisingly friendly, but it was also super weird.

There was also a halfway house on the corner near my wife’s office downtown. The cops were both way more hostile than necessary to the people who lived/frequented around there … but were also useless (and unnecessarily hostile) when someone from/near that building did do something like break into a car.

I spent some time working on a restorative justice theatre program nearby as well, where all the participants were transitioning out of prison and/or rehab. A lot of the people I met through that program had lived at that same halfway house at some point … and had nothing good to say about the slumlord collecting those Section 8 vouchers. Naturally (and understandably), they had nothing good to say about Ithaca cops either, and had had similar experiences to my wife’s office when actual victims of crimes tried to say “Hey can you help?”

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