“You have 60 more seconds." "You have 30 more seconds.”

The female voice interrupted each time Maria Marshall talked on the phone with her son in prison.

But the chance to make contact for three or four minutes a day, a few days a week, came with a cost. Marshall spent $120 in just two weeks in July for her son to call her and other relatives and friends.

“My son is just trying to get through it,” Marshall said a few weeks before he was released. NBC News agreed not to publish his name, age or what he was convicted of because he is still in his teens. “He’s afraid. He’s scared. It’s a traumatic experience. Talking to familiar people and his family is making that experience less traumatic.”

Maria Marshall and her son. Maria Marshall

Many states make millions each year in commission off phone calls that families like Marshall’s struggle to pay for. Inmate calling services are controlled by two main telecommunications companies, but the Federal Communications Commission says it does not have authority to set price caps on intrastate calls, which account for a majority of prisoner phone calls.

Some are now pushing for change. U.S. Sen. Tammy Duckworth, D-Ill., and five other senators have introduced a bill calling for “just and reasonable charges” for intrastate and interstate calling that would give the FCC authority to address inmate calling rates.

“This allows the FCC to regulate and say you can’t have predatory pricing,” Duckworth said. “Cause that’s what’s happening — predatory pricing.”

For Marshall and her son, who was imprisoned hours away from her in Washington state from January to July this year, the phone calls helped her make sure he was safe.

“For his own sanity, his own safety and my peace of mind as his mother, I need to hear from him,” Marshall said. “If I don’t hear from him, I worry.”

But some months, Marshall struggled to pay for the calls.

“These are not luxuries for a human being to be able to call their mother,” she said. “Their impact is also on the family members.”

Two companies, Securus Technologies, headquartered in Carrollton, Texas, and Global Tel Link in Falls Church, Virginia, dominate the prison telecommunications industry and have a large say in the cost of phone calls made by the 1.5 million men and women incarcerated nationwide.

Securus serves more than 3,400 correctional facilities in the United States, and Global Tel Link over 2,400.

A typical 15-minute prison phone call within Washington costs around $1.65, making it one of the more affordable states for such communications. On the other end of the spectrum, such a call in Kentucky costs around $5.70.

Marshall has been paying these charges for 13 years, since her ex-husband was sentenced to life without parole plus six years in a Colorado prison for first-degree murder and aggravated motor vehicle theft.

But putting money on both her son’s phone account and her ex-husband’s became too much, and she had to choose between the two. She chose her son's.

“It’s supporting my son’s humanity. Someone who’s coming back into the community,” Marshall said. “Humanized and connected to his family is helping make a reentry plan.”

An inmate talks on the phone at San Quentin state prison in San Quentin, California. Lucy Nicholson / Reuters file

Many people in prison are aware of the high price tag associated with staying connected to loved ones, said Spencer Oberg, who was imprisoned from 2011 to 2018 and is now CEO of Unincarcerated Productions, a company that aims to change negative attitudes toward prisoners and former prisoners.

Because of that awareness, he said, many incarcerated people discourage their family members from putting money on their phone accounts because they don’t want to be a financial burden.

“I couldn’t even count how many people I knew personally throughout my sentence that either their family members could not afford to put money on the phones so they could stay in touch, or the incarcerated person was not willing to put that burden on their family,” Oberg said.

The FCC attempted in 2013 to set new rate caps for interstate calls. The next year, it tried to establish a second cap to regulate intrastate calls.

But under the Trump administration and FCC Chairman Ajit Pai, the agency abandoned the argument that “the Commission has the authority to cap intrastate rates for inmate calling services,” in a letter to the U.S. District Court of Appeals for the District of Columbia Circuit.

The Human Rights Defense Center and other prisoners’ rights advocates argue the FCC’s decision benefited inmate calling services because it allowed them to continue charging the higher rates.

They also said the decision reflected a conflict of interest because one of Pai’s clients at the law firm Jenner & Block, where he worked before becoming chairman, was Securus Technologies.

“The D.C. Circuit has ruled that the FCC currently lacks the authority to regulate the rates of intrastate calls from prisons,” an FCC spokesperson said in a statement in July.

The FCC’s decision led to the current interstate calling rates and returned the amount providers can charge as fees to the interim caps set in 2013. The current cost of an interstate call is 21 cents a minute for debit or prepaid calls, and 25 cents a minute for collect calls. Additionally, providers can charge a $3 fee for automated payments, $5.95 to speak to a live agent and $2 for paper bills and statements.

In the absence of regulation on intrastate calls, states may enter into contracts with prison telecommunication companies and set their own prices. In making these contracts, states can earn a commission off the total revenue the inmate calling service collects on intrastate calls.

An inmate uses a telephone from a cell at San Quentin State Prison in San Quentin, California. Bloomberg via Getty Images file

Washington state collected $3.8 million in commission in 2017, or 56 percent of Global Tech Link’s intrastate revenue that year. The agreement remains in effect.

Ninety-two percent of prison phone calls are intrastate, allowing states to make millions off phone calls many struggle to afford.

“Our call rates are set based on contracts with individual states and counties, and details of those contracts are generally dictated by competitively bid, public RFPs,” Securus Technologies said in a statement, referring to request for proposals. “Most states and counties include commissions as part of those RFPs, which can account for as much as 90 percent of overall call rates.”

“Each jurisdiction determines how they use revenue from commissions, but many use them to help fund additional services for incarcerated individuals, including addiction workshops and educational courses.”

Global Tel Link declined to comment.

While not all states receive commissions, each contracts with a single prison telecommunications company, limiting prisoners and their families to that service only. The lack of consumer choice creates monopolies in each state, allowing the companies to charge whatever they want, critics say.

“The ultimate consumer of the service here, which is the prisoner, has no consumer choice,” said David Fathi, director of the American Civil Liberties Union's National Prison Project. “They can’t say, ‘Wow, these phone calls at this prison are too expensive’ and can’t switch.”

Bruce Reilly, deputy director of VOTE, a nonprofit run by formerly incarcerated people and their family members that works to help those affected by the criminal justice system, was incarcerated in Rhode Island from 1993 to 2005. He called the system monopolistic and immoral.

“Nobody else negotiates my grocery prices. Nobody else decides which cellular phone provider I use or Roku or HBO,” Reilly said. “That’s my choice as the user. Here, you’re incarcerated in prison, and someone else is negotiating for you.”

Paul Wright, director of the Human Rights Defense Center and editor of Prison Legal News, said the system gives prisoners no options.

“The alternative is they don’t talk to their family,” Wright, who was incarcerated in Washington from 1987 to 2003, said.

For David Moore, phone calls have been his lifeline. He was 20 years old when he was sentenced to 18 years in prison for assault, a drive-by shooting and other convictions.

His son, now 10, was born when he began serving time, but through phone calls and prison visits, Moore has been able to co-parent his child.

“There’s been times that I’ve had to trade away my personal hygiene — deodorant, toothbrush, soap, food, just to try and call my son,” he said.

That connection to loved ones and the outside world is a significant factor in a successful reentry into society after a prisoner is released, studies show. Prisoners who had family support during their incarceration were less likely to be back in prison after rejoining their communities.

“When people get out, they’re gonna live in your town,” Reilly said. “The more connectivity they have, the more network, the more opportunity, the more people who love them, the better off those folks are.”

The situation may be slowly changing. Connecticut Rep. Josh Elliott, D-Hamden, introduced a bill in the state Legislature this year that would make phone calls for prisoners free. Although the bill died when the legislative session ended, he said he is hopeful it will get taken up again in the spring.

If approved, Connecticut would be the first state to offer free calls, but its Department of Corrections would lose about $350,000 a year in telephone contract proceeds.

Even so, department Commissioner Rollin Cook said he is committed to family engagement and wants to reduce the financial burden phone calls place on families.

“It’s the right thing to do,” Cook said in a statement. “We should not be making it more difficult for families to stay connected with an incarcerated loved one. Family connections are a critical component of successful reentry.”