Saturday, February 21, 2009

Polygraphs are junk science no matter who uses them, or why

If polygraphs are so unreliable they're not admissible in court, are they really a good tool for pre-employment screenings for law enforcement? The Austin Statesman offered up an alarmist report this week ("Admitted scofflaws, poly flunkers among DPS recruits," Feb. 19) that, at the Department of Public Safety:

Some members of the current recruit class of more than 100 failed polygraph tests on their background.

“More than a handful” were rejected by other law enforcement agencies before they applied at DPS.

Others have been promoted from the training academy and put to work despite a recommendation that they be dismissed.

Some recruits in the past even got in despite admitting criminal behavior of some type during interviews.

“Wow!” exclaimed Commissioner Ada Brown of Dallas.

Despite some recruits’ deception on the agency’s polygraph tests, “you give him a badge? I have a problem with that.”

Certainly it's problematic if troopers are given a badge over the recommendation of those who trained them, or if they've admitted to serious, past criminal activity.

But if someone was rejected by another department because that agency thought they found a better candidate, that shouldn't in and of itself disqualify someone from working for DPS. (If they were rejected for some specific cause, that's a different matter.)

Equally unfair would be to rely on polygraph testing, which amounts to junk science at its worst, to deny potential troopers employment. I don't know why anyone still thinks these things are reliable. As one critic put it, "There's something about us Americans that makes us believe in the myth of the lie detector. It's as much of a myth as the Tooth Fairy."

I'm as concerned as anyone on the Public Safety Commission about misconduct by state troopers, which is why I believe DPS' Internal Affairs division should be substantially beefed up. But denying someone employment because they "flunk" a polygraph test - or for that matter relying on polygraph results to discipline officers - is bad public policy with no legitimate scientific basis.

IMO, DPS should toss its polygraph machines on the junk pile and instead focus on more exhaustive background checks performed by actual human beings if they want to prevent bad apples from becoming state troopers.

18 comments:

Shane said...

Polygraphs are common for employees in my line of work. They're ridiculous. From what I've seen, people who fail are given nearly an infinite number of chances to pass. It seems the decisionmakers know that a polygraph "failure" doesn't mean anything. And yet they are still part of policy, for access to sensitive information. It's a waste of tax dollars. Between the significant rates of false positives and false negatives, I fail to see any value.

Soronel Haetir said...

Oh but don't you get it? What would all the poor polygraph examiners do if their previous equipment got dumped on the junk heap of history? They would have to go find actual work. We can't have that, government employees have that perpetual employment clause after all, even in the face of misconduct most of the time.

lowery.shirley said...

Paroled sex offenders must pay $250 for regular testing. Failing the test, as I understand it, means a trip back to prison without an order from a Judge.

Anonymous said...

Actually Shirley, The Parole Officer has to put in the paperwork to revoke, but that is strictly an afterthought thing. Most revocations put in by P.O.'s will gain the 'offender' a fast and expeditious trip back to the pokey usually with little or no evidence.

The polygraph is the only item I know that is considered 'scientific' but relies completely on subjective opinion of the person who asks the questions.

They use a school grade ruler for Christ's sake to grade 'deception'...

Anonymous said...

I think Scott should apply to work for DPS. I'm sure he can really straighten things up at DPS.

Poly's are useless in screening applicants, even more useless if you don't weed out the failures.

Anonymous said...

But they are OK for internal affairs investigations of current officers, right?
If there is no evidence against an officer, and he fails a poly, then he is guilty....and fired.

Anonymous said...

Good story, you should post it on this website blog:

http://antipolygraph.org/

Anonymous said...

Why the hell would any sane person want to work for the State of Texas in any capacity?

jimbino said...

Polygraphs are no more idiotic than religion, which is subscribed to by some 90% of the voting populace, though it has no basis in reason or science whatsoever.

Indeed, if the Texas Constitution says you can't be a lawyer or juror unless you believe in a Supreme Being, why shouldn't courts just rely on entrails and polygraphs for evidence?

Aine O'Brocken said...

Polygraphs are junk science--yet our culture depends heavily in them in many ways.

PAS [Parental Alienation Syndrome]is also junk science, created by a man named Gardner, who believed that having sex with children was permissible [in other words, molesting children, according to Gardner was a positive practice]--and might, in fact be a practice that the children would learn to enjoy.

The difference between the junk science of the polygraph and the junk science of PAS? PAS is admissible in court. Du-uh!

Anonymous said...

There is so much abuse and corruption in DPS, that its only right to use these tests against obviously criminal patrolmen. Something needs to be done to stop their out of control behavior. Abolish DPS.

Anonymous said...

What about the closing of the West Texas State School? Is 75 employees being laid off? What a tragedy...why no story?

Anonymous said...

Polygraph is not admissable in criminal court proceedings. It is just another tool in the larger toolbox for investigators. No state employee is ever forced to take a polygraph or be fired, after they are hired. The use of them in pre-employment capacities is another matter. No polygraph examiner, worth their salt, will ever err on the side of a liberal interpretation. There are some, who you see on television shows, doing a very sloppy job with the pre-interview (if they even bother). Polygraph has many, many limitations and should never be the sole basis of any investigative conclusion. It is useful however as an investigative tool from several points of view. Often, the psychological impact of being placed on the machine, will produce some useful information for the investigator that would have been difficult or impossible to obtain without the polygraph. It also allows investigators to sometimes eliminate a person as a suspect. No investigator worth their salt, uses the polygraph alone to establish a person as the guilty or innocent party. It's meant to be one element in an investigation. Like anything else, the integrity of the process is highly dependent on the training of the polygrapher, his or her level of individual competence, etc. Many polygraphers are already trained investigators, prior to becoming trained in polygraphy. The course of study is extremely regororous. It is true, that continued attempts to validate or invalidate the polygraph process should help to refine it to eliminate unproductive methods, interpretations, and abuses. But it still remains viable as an investigatory tool. The important thing is not to use the polygraph to validate someone's foregone conclusion.

Anonymous said...

Charles Kiker to Jimbino:

Sounds to me like you have an axe to grind and just saw this post as a convenient grindstone. (Often to people with axes to grind, everything looks like a grindstone.) I don't know that faith or the lack thereof is ever used as a criteria for guilt or innocence. The only time faith or the lack thereof should be an issue in employment is if the employer is a church or some other specific faith-based organization. And not then if the position is government funded. Faith or the lack thereof should never be an issue in government hiring. And faith or the lack thereof should not be smuggled in to a discussion about the validity of polygraphy.

h4 said...

Polygraphs and much else is junk science:

Congress asked the National Academy of Sciences to evaluate our national forensics labs. I doubt Congress expected the results would be so bad. The NAS report says that the only forensic evidence that is reliable is DNA -- fingerprints, blood spatters, hair/fiber, ballistics, bite marks, etc. all have limited scientific basis, and limited studies to determine reliability. And having crime labs run by cops exacerbates the problem. The report recommends further research, and creation of an independent National Institute of Forensic Science.

You can read their news release at http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=12589, and the full report in segments at http://www.nap.edu/catalog.php?record_id=12589#toc

Anonymous said...

"No investigator worth their salt,"
.........
would ever waste their time on using a polygraph on a professional crook. Most of whom are pathological liars and would pass with flying colors.

Anonymous said...

State agencies find ways to hire and retain some of the most undesirable people and to fire or run off the best employees. They never seem to catch on that their hiring practices consistently fail. Beyond that they are more likely to fire employees for the most minor infractions and retain those committing serious infractions. It is obvious that DPS does the same thing. In my little county we have had some highway patrolmen who terrorized the citizens at night. They would hide on gravel roads and stop people for being suspicious, by driving on a gravel road at night. They accused everyone of transporting and or cooking cooking drugs and browbeat them into consenting to a search.

Don Dickson said...

I told Mike Ward and Allan Polunsky, too, that I was ELATED to hear that DPS had hired numerous people who had failed pre-employment polygraphs. That tells me (A) that even DPS recognizes that they are as much art as science, (B) that they are not foolproof, and (C) that DPS isn't kidding when they insist that a polygraph is an investigative TOOL, not a SUBSTITUTE for an investigation.

One commenter noted, and it bears repeating, that DPS is prohibited by law from requiring one of its officers to be subjected to a polygraph examination. The Legislature authorized the use of pre-employment polygraphs.

A few years ago DPS changed the form used for pre-employment background investigations. The Trooper who conducts the investigation and the sergeant who conducts the home study used to be able to express their opinions, but in recent years nobody below the rank of major was given an opportunity to give a recruit a thumbs-up or thumbs-down. I think you can expect the form to get changed back the way it was pretty soon.