The Bureau of Prisons charges inmates to make calls on its landline phones and records all of the calls. According to the GAO's investigation, the Bureau's rates are typically lower than in state or military institutions.
The Bureau of Prisons uses the revenue from telephone calls to cover various inmate amenities. The GAO did not recommend that the Bureau of Prisons lower its phone rates to discourage inmates from using contraband cellphones.
Prison officials use metal detectors to screen for contraband, including cellphones, and two prisons uses sensor-based cellphone detection systems, according to the report.
The GAO cited a previous National Telecommunications and Information Administration study that found cellphone jamming can interfere with signals outside of the prison and that nonfederal agencies do not have the authority to jam cellphone calls.
CTIA, a wireless trade group, praised the GAO for not endorsing cellphone jamming.
“The GAO does not recommend jamming, and in fact is consistent with our view that jamming wireless signals can cause interference to cellphone signals outside of a prison institution and violates the Communications Act," said CTIA CEO Steve Largent. "CTIA and its members support efforts to prevent the smuggling of contraband phones into correctional facilities and will continue to work with the appropriate authorities to combat this problem."