According to the reports from American media, a prison in Maryland tested a set of cell phone jammer in 2010 with the approval of the Federal Communications Commission and the Federal Bureau of Investigation. Martin O'Malley, the Maryland Governor hoped to persuade Congress to permit the use of mobile phone jammer in prisons to prevent criminals using mobile phones.

In the United States, it has become a common practice that prisoners establish illegal contact with outside through mobile phones. In 2007, a criminal in the Maryland prison contacted with outside criminal organization to kill a witness. In 2009, a Texas Senator was intimidated by a prisoner with a phone in prison.
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Associated Press reported that 26 states in the United States jointly submitted an application to the Federal Communications Commission in July of 2009, which asked Federal Communications Commission to approve the application of mobile phone signal jammer in the prison. In the United States, The non-governmental radio communications are under the jurisdiction of Federal Communications Commission.

It is not a new concept to install mobile phone signal jammers in prison. This technology can effectively prevent prisoners from using smuggled mobile phones to continue to engage in illegal activities. But some critics believe that the use of cell phone signal jammer in the prison may affect the safety of the communication of nearby area.