DEC. 09 

U.S. Department of Justice 

Office of Justice Programs 

National Institute of Justice 

Toward Criminal JusTiCe soluTions 

IN 

short

NCJ 227539 

Cell Phones Behind Bars 

A widespread technology that allows people to 

connect with anyone, anywhere, has created 

concerns for corrections officials. The use of inexpensive, disposable cell phones has changed 

the age-old cat-and-mouse game of controlling 

whom inmates communicate with in the outside 

world and is creating serious problems for public 

safety officials. 

In the 1990s, cellular phones were larger and 

heavier and had audio capabilities only. Today 

they are lightweight, can be thinner than a matchbook, and can send both audio and data, including 

written messages and streaming video. Although 

these advances are welcome in society in general, they have had a negative impact on the law 

enforcement community, as criminals have taken 

advantage of cellular technology to conduct illegal 

activities. 

A WidespreAd problem 

The issue of cellular phone use by criminals, 

especially prison and jail inmates, gained national 

attention when a death row inmate used a cell 

phone to threaten a Texas senator. In Nevada, 

prison officials fired a dental assistant for helping 

an inmate get a cell phone to plan a successful 

escape. In New York, an inmate used a cell phone 

to orchestrate an attempted escape while on a 

medical transfer. In Tennessee, prison officials 

banned jars of peanut butter after learning that an 

inmate accused in the shooting death of a guard 

had used a jar to hide the cell phone he used to 

coordinate his escape. Prisoners have also used 

cell phones to harass and threaten their victims. In 

Texas, courts have convicted more than a dozen 

corrections officers in recent years for accepting 

bribes in exchange for cell phones or phone parts. 

ContrAbAnd 

The number of contraband cell phones being 

confiscated is also noteworthy. For example, in 

California, correctional officers seized 1,331 cell 

phones in the first six months of 2008. Corrections 

officials in other states have also reported finding 

hundreds of cell phones. 

Corrections officials have spent millions of dollars 

to outfit prisons and jails with metal detectors, 

but the detectors do little to stem the flow of cell 

phones from the outside. Some cell phone parts 

are made of plastic and go undetected. 

shutting doWn Cell phones 

Blocking cell phone service involves using technologies to stop the transmission or reception 

of other radio signals. In some cases, blocking 

signals can be tuned to leave specific frequencies open, which would allow for communication 

among corrections personnel, or they can block 

almost all signals. The power of the blocking 

signal determines how large an area is affected. 

The area could be as small as a cell block or large 

enough to cover an entire prison. Blocking systems can cost as little as $1,000, but more powerful systems can cost tens of thousands of dollars. 

Another technology allows for spoofing cell 

phone signals. Spoofing involves intercepting 

selected cell phone transmissions and preventing them from reaching the intended recipient. 

Spoofing uses sophisticated software and is 

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possible without the active participation of the cell 

phone network providers. A drawback to selective 

blocking and spoofing is the potential for inmates 

to use approved cell phones that belong to staff 

members. 

FederAl government rules 

The Communications Act of 1934 and the 

Telecommunications Act of 1996 prohibit the 

operation of cell-phone-jamming equipment by 

any person, including state and local officials. 

Specifically, Section 333 of the Communications 

Act prohibits willful or malicious interference with 

any licensed or authorized radio communications 

equipment or with radio equipment operated by 

the United States government. In addition, the Act 

prohibits the manufacture, importation, marketing, 

sale or operation of devices deliberately designed 

to jam or disrupt wireless communications. 

Legislation in Congress titled the Safe Prisons 

Communications Act of 2009 would let prisons 

and jails use cell-phone-jamming technology. 

Countering the problem 

As they await legislative relief from the problem, 

corrections officials are using various technologies that detect and find cell phones. Both 

high-technology and low-technology approaches 

are being tested and used. Several agencies 

have installed sensors that detect and find cell 

phones when in use. One such device tested in a 

Pennsylvania prison signaled cell phone location 

to within four cells on two tiers. Some sensors 

can even detect cell phones that are turned off, 

but they only work when in close proximity to a 

phone, cost between $15,000 and $20,000, and 

require trained staff. Others use new detectors 

that can identify nonmetallic objects to conduct 

searches. For smaller facilities, the use of specially 

formulated paints and coatings that block radio 

frequency signals may help. 

Some correctional institutions use specially trained 

dogs to sniff out hidden cell phones. These efforts 

have not been rigorously evaluated. Dog training 

can cost tens of thousands of dollars. Dogs must 

be close to the phone, and anecdotal evidence suggests that the phone must be left in the same place 

for a considerable time to be found. 

Most of these solutions are expensive and labor 

intensive. Each would benefit from a thorough 

evaluation. 

For more information about NIJ’s Communications 

Technology program, see http://www.ojp.usdoj.gov/ 

nij/topics/technology/communication/welcome.htm. 

*NCJ~227539*
 

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