Archer Blackwell, a member of the AFSCME unit that represents officers at the jail, said the union likes the technology.

"That's very much needed," he said.

A state legislative commission that was established to propose security improvements after the federal indictments wants to expand the use of cellphone blocking. The lawmakers aimed to provide funds for it at the detention center first, and other jail facilities in the Baltimore area in coming years.

Del. Guy Guzzone, the Howard County Democrat who co-chairs the commission, said he was "incredibly pleased" the system is now online.

"It is a good deal to handle a very serious problem," he said.

Binetti said the technology would be installed at other institutions in the state prison system as needed. He said the governor's budget includes money to deploy managed access to other secure facilities in Baltimore.

Binetti said it's too early to tell what effect the technology has had on the flow of contraband or other illegal activities at the jail. But he said the state has an idea of its effectiveness from the long lines at the authorized pay phones at the transition center.

"The use of those phones has skyrocketed since that managed access system is up and running, and we expect to see the same at BCDC," he said.