Maryland did not join the petition because it had its own effort under way, Maynard said.
Last month, Mikulski and Gov. Martin O'Malley sent a joint letter to the National Telecommunications and Information Administration asking for its participation in a half-hour demonstration of cell-signal jamming.
"We are not asking that the NTIA ... take a position on the proposed federal legislation at this time," the June 15 letter reads. "We are simply requesting that the NTIA allow this demonstration to occur."
After four weeks, there has been no reply, O'Malley's spokesman said.
Critics say that jamming, which prevents cell phone signals from communicating with transmission towers, is not an exact science and could interfere with emergency communications and other legitimate use. They point to radio frequency detection technology such as that made by ITT Corp. in Columbia, saying it is less expensive and would provide better results.
Others disagree.
Howard Melamed, who sells jamming technology abroad through his Florida-based company, CellAntenna Corp., said he can block signals in specified areas, including a pocket.
"It may not be as beneficial as we think," Maynard said. "But we don't know. We haven't been able to see it tested.
Cell phones in prisons
California: Contraband cell phone collection doubled to 2,800 in 2008.
Kansas: Cell phones were used to plan two unsuccessful escapes.
Massachusetts: An inmate made a threatening call to a medical staff member, trying to get her to smuggle in weapons.
Nevada: An inmate used a cell phone to plan his escape, then committed three home robberies, a kidnapping and car theft.
South Carolina: Inmates used cell phones to steal thousands of dollars through credit card fraud.
Texas: A death row inmate used a cell phone to make a threatening call to a lawmaker.
Washington: Fired correctional officers face prosecution for smuggling phones.
West Virginia: A Hazelton correctional officer was recently indicted for smuggling a phone into a federal facility.
- Maryland Department of Public Safety and Correctional Services
