so this guy sound weird but a few years
ago the NYPD used facial recognition to
catch a shoplifter and they didn't even
have a clear picture of his face the
clerk said the guy kind of looked like
the actor Woody Harrelson so they just
pulled up a photo of Harrelson and put
it in the system it worked they caught
the guy it turns out he really did look
like Woody Harrelson
but facial recognition systems were
never built to be used this way and
incidents like this raise the question
of whether police should have this
technology at all it's not the only time
something like this has happened this
past year Georgetown University
conducted a study of some of the use
cases and they're pretty wild some
police departments have actually pasted
it in different facial features in an
effort to get the system to produce a
match if the left eye is blocked in your
picture just paste in a new left eye if
the suspects mouth is open paste in a
new mouth that's closed these are
delicate algorithms but in most cases
there are no strict rules for how police
use the algorithms and whenever the
machine produces can be used as grounds
for a police stop okay but before we get
into that let's talk about how facial
recognition really works at its core
facial recognition is about tracking key
facial landmarks from photo to photo the
distance between your pupils the angle
of your nose the shape of your
cheekbones basically all the details of
your face that make it distinctive that
works best from a straight-on photo with
at least 80 pixels between the pupils
think like a passport photo or a
driver's license but once you've got
that basic pattern sophisticated
programs can recognize the same features
at an angle it can even work if part of
your face is blocked as long as there
are two pupils and enough other features
to be sure vendors like any see more fo
and cognate XP an ear D systems selling
their software to local and federal
police forces but in the past few years
Amazon and Google have been building it
into their computing clouds too which
makes it a lot easier to get with a
couple hundred bucks and some coding
skills almost anyone can create a facial
recognition system these programs work
off accuracy thresholds the tighter the
match the higher the number but there's
no firm rule about how high the number
needs to be which means that the same
time police are playing with the photos
they upload
to the system they're also playing with
the standard for what counts as a match
so if you look like Woody Harrelson even
a little bit an officer could adjust the
accuracy threshold until it registers is
a hit and then if you ask why you're
being stopped they can just say the
Machine said it was you if you talk to
the people making these tools you're
really not supposed to do any of this
it's like steering a car with your feet
you can make it work but it's bizarre
and dangers and with police the end
result of all of that is stopping
someone maybe for no reason that's even
worse because the algorithms are less
accurate for women and people of color
it's not totally clear why that's true a
lot of people think it's just a result
of algorithms that are mostly trained on
white men but government testing shows
it really consistently across the
industry you can see on this chart the
red lines are the error rate for black
people and the green lines of the error
rate for white people the red lines are
almost always higher which means the
person getting stopped for no reason is
more likely to be from a community at
risk now the NYPD says that no one has
been arrested on the basis of facial
recognition alone and that's true but
facial recognition has been involved
somehow in more than 2,800 arrests in
the five and a half years the program
has been running even when there's no
arrests at all the false match can still
lead to a police stop which has dangers
of its own there's supposed to be a
clear legal bar for making those stops
but facial recognition is
short-circuiting that now defenders
official recognition will say that
despite the problems it's still an
effective tool for police to protect our
communities
Detroit's project greenlight is a
network of connected surveillance
cameras recently upgraded with facial
recognition and it's credited with a 23%
drop in crime in the city but it's still
controversial some community members say
there's no transparent oversight and the
flood of new tips is overwhelming the
police force
the fights gotten really heated so
heated that one of the city's police
commissioner's was actually arrested at
a hearing trying to speak out against
the system other cities have passed
local laws banning the use of facial
recognition by police for just that
reason
San Francisco home to some of the
largest tech firms in the world banned
it last year San Francisco supervisor
Peskin was particularly critical calling
it big brother technology but this isn't
just a tech problem fundamentally San
Francisco's saying the government just
can't be trusted with this technology
not because it's so bad but because we
don't have enough oversight over how
police departments will actually use it
that's a problem that goes much deeper
than just recognizing faces and as we
find more powerful ways to peer into the
average person's life it's a problem
that's not going away thanks for
watching like and subscribe if you want
some more and if you're looking for
another video my colleague Casey Newton
has an incredible report about Facebook
moderators and just what a difficult and
disturbing job it is so check that out