The small and surprisingly dangerous detail the police track about you

A very unsexy-sounding piece of technology could mean that the police know where you go, with whom, and when: the automatic license plate reader. These cameras are innocuously placed all across small-town America to catch known criminals, but as lawyer and TED Fellow Catherine Crump shows, the data they collect in aggregate could have disastrous consequences for everyone the world over.

The shocking police crackdown
on protestors in Ferguson, Missouri,

in the wake of the police
shooting of Michael Brown,

underscored the extent to which advanced
military weapons and equipment,

designed for the battlefield,

are making their way

to small-town police departments
across the United States.

Although much tougher to observe,

this same thing is happening
with surveillance equipment.

NSA-style mass
surveillance is enabling

local police departments
to gather vast quantities

of sensitive information
about each and every one of us

in a way that was
never previously possible.

Location information can
be very sensitive.

If you drive your car around
the United States,

it can reveal if you go
to a therapist,

attend an Alcoholics Anonymous meeting,

if you go to church
or if you don't go to church.

And when that
information about you

is combined with the same information
about everyone else,

the government can gain
a detailed portrait

of how private citizens interact.

This information used to be private.

Thanks to modern technology,

the government knows far too much
about what happens behind closed doors.

And local police departments make
decisions about who they think you are

based on this information.

One of the key technologies
driving mass location tracking

is the innocuous-sounding
Automatic License Plate Reader.

If you haven't seen one,

it's probably because you didn't
know what to look for --

they're everywhere.

Mounted on roads or
on police cars,

Automatic License Plate Readers
capture images of every passing car

and convert the license plate
into machine-readable text

so that they can be checked
against hot lists

of cars potentially wanted
for wrongdoing.

But more than that, increasingly,

local police departments
are keeping records

not just of people wanted for wrongdoing,

but of every plate that
passes them by,

resulting in the collection
of mass quantities of data

about where Americans have gone.

Did you know this
was happening?

When Mike Katz-Lacabe asked
his local police department

for information about the plate
reader data they had on him,

this is what they got:

in addition to the date,
time and location,

the police department had
photographs that captured

where he was going and
often who he was with.

The second photo from the top
is a picture of Mike and his two daughters

getting out of their car
in their own driveway.

The government has
hundreds of photos like this

about Mike going about his daily life.

And if you drive a car
in the United States,

I would bet money
that they have photographs

like this of you going
about your daily life.

Mike hasn't done anything wrong.

Why is it okay that the government
is keeping all of this information?

The reason it's happening is because,

as the cost of storing
this data has plummeted,

the police departments
simply hang on to it,

just in case it could be useful someday.

The issue is not just that
one police department

is gathering this information in isolation

or even that multiple police
departments are doing it.

At the same time, the federal government

is collecting all of these
individual pots of data,

and pooling them together
into one vast database

with hundreds of millions of hits,

showing where Americans have traveled.

This document from the
Federal Drug Enforcement Administration,

which is one of the agencies
primarily interested in this,

is one of several that reveal
the existence of this database.

Meanwhile, in New York City,

the NYPD has driven police cars
equipped with license plate readers

past mosques in order to
figure out who is attending.

The uses and abuses of this technology
aren't limited to the United States.

In the U.K., the police department

put 80-year-old John Kat
on a plate reader watch list

after he had attended dozens of
lawful political demonstrations

where he liked to sit on a bench
and sketch the attendees.

License plate readers aren't the
only mass location tracking technology

available to law enforcement agents today.

Through a technique known as
a cell tower dump,

law enforcement agents can
uncover who was using

one or more cell towers
at a particular time,

a technique which has been known to reveal

the location of tens of thousands
and even hundreds of thousands of people.

Also, using a device known as a StingRay,

law enforcement agents
can send tracking signals

inside people's houses
to identify the cell phones located there.

And if they don't know
which house to target,

they've been known
to drive this technology

around through whole neighborhoods.

Just as the police in Ferguson possess
high-tech military weapons and equipment,

so too do police departments across
the United States

possess high-tech surveillance gear.

Just because you don't see it,

doesn't mean it's not there.

The question is, what should
we do about this?

I think this poses a serious
civil liberties threat.

History has shown that once the police
have massive quantities of data,

tracking the movements of innocent people,

it gets abused, maybe for blackmail,
maybe for political advantage,

or maybe for simple voyeurism.

Fortunately, there are steps we can take.

Local police departments can
be governed by the city councils,

which can pass laws requiring the police

to dispose of the data
about innocent people

while allowing the legitimate
uses of the technology to go forward.

Thank you.

(Applause).