
Homeland Security's 'Pre-Crime' Screening Will Never Work - spathak
http://www.theatlantic.com/technology/archive/2012/04/homeland-securitys-pre-crime-screening-will-never-work/255971/
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jessriedel
So the obvious problem with the movie _Minority Report_ was the false
dichotomy between (a) imperfectly predicting crimes and then punishing people
before they commit them and (b) not predicting crimes. The obvious third
choice, which has been in use since time immemorial, is (c) imperfectly
predicting crime and then applying normal crime-prevention measures to
increase the chance of catching the perpetrator and/or reduce the chance that
the crime is committed at all, while simultaneously using less resources. In
any sane world, the technology of _Minority Report_ would still be used to
reduce murders through direct intervention and the deterrent of more effective
enforcement, without taking people off to pre-crime prison.

The author's implication that FAST is an implementation of the obviously-bad
idea of punishing people for crimes they haven't yet committed is just one of
the many bad and misleading aspects of this article.

~~~
roc
Indeed. I read FAST as a sort of olive-branch in security theatre. It seems
that it, or something like it, will be used to remove porno-scanners and
grope-checks from standard security. If 70% of people are passing through
security without being hassled, their PR problems nosedive.

And frankly, though it's likely to be error prone and leave airport security
still largely ineffective, at least it's move toward trying to _intelligently_
identify risks. Rather that simply sending every single person through
ineffective security. And lessening the load on the scanners and gropers can
only raise their effectiveness.

~~~
Lagged2Death
_...will be used to remove porno-scanners and grope-checks from standard
security._

Has this ever happened? Has the TSA ever given up on a security screening
practice that had become a widespread routine?

 _If 70% of people are passing through security without being hassled, their
PR problems nosedive._

If 70% of passengers walk through the screening point without removing their
shoes, without walking through a metal detector, without having their bags
x-rayed, etc., and the other 30% are singled out for special treatment, won't
that 30% feel extra persecuted? The TSA's PR problems are mainly related to
rarer-that-30% outrages like selecting comely young women for pornoscanning,
interfering with uncommon medical equipment, etc.

~~~
roc
> _"Has this ever happened?"_

No, but I don't think the current state of things is sustainable. There isn't
a demographic that's free of TSA horror stories anymore.

And we all know a new vector will be chosen that will defeat these measures.
Thus, without a way out, the TSA will have to come up with an _even-more-
invasive_ screening method. And I can't see how that's at all feasible.

Drastically reducing the number of people who have to be subject to "advanced"
security measures through technology is a face-saving and politically-feasible
way for the TSA to back off. It's, frankly, their only way out.

As to the 30% feeling persecuted: yeah, probably. Particularly if a given
population consistently gets selected for 'advanced' security. [1] And
hopefully that's an avenue that can be leveraged to take further steps toward
sane security that doesn't infringe our liberties.

I'm not suggesting this is acceptable as a _solution_. Just as a step.
Provided it is, indeed, a step away from running every single person through
the current gauntlet of invasive TSA security theatre.

------
tptacek
This is a good article marred by, I think, a poor story angle. FAST sounds
like a terrible idea, but not because it's Orwellian.

Homeland Security is not primarily a law enforcement agency. Here are it's
departments; departments with a principle law enforcement focus are starred:

    
    
        Immigration Services 
        (+) ICE
        (+) Customs
        (+) TSA
        Coast Guard
        (+) Secret Service
        FEMA
        Homeland Security Advisory
        National Infrastructure Advisory
        Homeland Security Science/Technology
        Critical Infrastructure Partnership Advisory
        Interagency Coordinating Council on Emergency Preparedness
        Task Force on New Americans
        Domestic Nuclear Detection Office
        Federal Law Enforcement Training Center
        National Protection and Programs Directorate
        (+) Federal Protective Service
        National Communications System
        Directorate for Science and Technology
        Directorate for Management
        Offices of Policy; Immigration Statistics; Health Affairs
        Offices of Intelligence and Analysis; Operations Coordination
        Office of the Secretary
        National Cyber Security Center
    

(Yes, DHS is a monster, everyone knows that; we should definitely slay it).

People who have worked on the intrusion detection problem in computer systems
are well familiar with the Base Rate Fallacy (what this article appears to be
talking about when it mentions the "false positive fallacy"). To anyone who
has actually monitored a deployed IDS, the base rate problem is a killer.
_Most of the events generated by systems like this are mathematically certain
to be bogus_.

So it's great to see an Atlantic article trying to tackle the numeracy issue
here: DHS policymakers looking for research funding are bragging about a
terrorist detection system with a 70% accuracy rate, and 70% sounds great when
you leave out the base rate of terrorism.

On the other hand: of the LEO functions of DHS, most of them fall into one of
two categories:

* Departments that already have total discretion to ignore civil liberties, like Customs: it's hard to imagine any new program making Customs more intrusive, because Customs operates under the border search rule (since at least 1976, Customs can set up any search program it wants to protect the integrity of the US border).

* Departments that operate under administrative search regimes, like TSA, where "behavioral monitoring" is if anything _less_ Orwellian than the systems already in place.

DHS research projects do not automatically imply that local and state police
will be deploying "behavioral" technology to "pre-crime" people. Again the
theme: when you argue against something, you need to be both right _and
correct_. "Pre-crime" is an inaccurate framing device.

------
bobbydavid
From the article:

"Nature reported that the first round of field tests had a 70 percent accuracy
rate. From the available material it is difficult to determine exactly what
this number means. There are a couple of ways to interpret this, since both
the write-up and the DHS documentation (all pdfs) are unclear."

I'm glad he pointed this out.

"This might mean that the current iteration of FAST correctly classifies 70
percent of people it observes -- which would produce false positives at an
abysmal rate, given the rarity of terrorists in the population."

But maybe this isn't so bad if it means that 70% of people aren't molested in
the airport, at the cost of missing 30% of terrorists we would otherwise
catch. I'm very okay with this: I see this as (1.73 * 0.7)-million happier
citizens per day [1] and (0 * 0.3) additional terrorist incidents [2].

"The other way of interpreting this reported result is that FAST will call a
terrorist a terrorist 70 percent of the time. This second option tells us
nothing about the rate of false positives, but it would likely be quite high.
In either case, it is likely that the false-positive paradox would be in full
force for FAST, ensuring that any real terrorists identified are lost in a sea
of falsely accused innocents."

The author is too smart for his own good here. The second interpretation
_should_ be "FAST will call a terrorist a terrorist 70 percent of the time.
What's a false positive?"

Those unfamiliar with statistics may incorrectly see it this way. Seventy
percent of terrorists will be caught, so that means we'll be more than 3 times
safer than we already are! Such statistical incompetence is also strongly
correlated to politicians. I can't back that up, though, due to my statistical
incompetence.

[1] [http://www.quora.com/How-many-people-fly-domestically-in-
the...](http://www.quora.com/How-many-people-fly-domestically-in-the-United-
States-each-day)

[2]
[http://www.gather.com/viewArticle.action?articleId=281474978...](http://www.gather.com/viewArticle.action?articleId=281474978709836)

------
read_wharf
Assuming honest research can achieve any of this in the foreseeable future,
does anyone expect DHS to conduct or oversee research honestly and
competently?

