When Sen. Kamala Harris, D-CA, was a law student, she clerked at the district attorney’s office in Alameda County, California. This was in the late ‘80s, in the middle of the crack epidemic, and Harris was tasked with processing cases from a major drug bust on a Friday afternoon. One arrestee was an “innocent bystander,” a woman with young children, Harris said in opening remarks at a Washington, D.C. conference on incarcerated women on Tuesday. The woman’s case probably wouldn’t go before a judge until that Monday, leaving her to sit in jail for the weekend. She might miss work or lose her job. If there was no one to care for her children, they might be seized by Child Protective Services.

Harris was able to find a judge to release the woman “with the swipe of a pen,” demonstrating for the future attorney general how easily a life can be derailed or disrupted—or not—in the banal, everyday workings of a system that currently holds more than 215,000 U.S. women in prisons and jails. “In the criminal justice system, individuals have so much discretion,” she said. “I, as a 20-something-year-old law student, could make a decision about someone’s liberty and life.”

As a U.S. senator, Harris is trying to do more. Last week, along with fellow Democratic Sens. Elizabeth Warren, Cory Booker, and Dick Durbin, Harris introduced the Dignity for Incarcerated Women Act, an ambitious bill that would enact much-needed reforms in the treatment of women in federal prisons. A few of the bill’s provisions cover issues of basic safety and dignity: It would ban the shackling of pregnant women, prevent officials from putting pregnant inmates in solitary confinement, and require prisons to provide free menstrual products to inmates, who currently may be given limited supplies or made to buy their own. Male guards would no longer be allowed to supervise female inmates in bathrooms except during emergencies, and inmates would no longer have to pay to call friends and family members.

Other parts of the bill target incarcerated mothers, who have a special set of needs. About 65 percent of women in U.S. prisons and jails have children under 18, and most are primary caretakers. According to Holly Harris, executive director of the Justice Action Network, the convener of Tuesday’s forum, one in four women who become incarcerated are pregnant or have a child under the age of 1. The Dignity for Incarcerated Women Act would require the Federal Bureau of Prisons to take children’s locations into account when choosing a facility for an inmate who is a parent. Inmates who are pregnant or primary caretakers would also be eligible for a residential drug abuse program. The bill would also provide for more generous visitation hours, physical contact in visits, parenting classes, and a pilot program for overnight visits. About half of incarcerated mothers in the U.S. are more than 100 miles from their families, and the facilities where they’re held are often in remote locations, “not on the commuter line,” Sen. Harris noted in her remarks. Andrea James, the formerly incarcerated founder of an advocacy organization for incarcerated women and girls, says mothers in prison serve a “dual sentence,” because they spend their time locked up worried about their children’s well-being. “The lives of their children do not get better” with their mothers gone, James said at Tuesday’s conference. “It causes further harm.”

But if the Senate bill passes, it will only apply to the 12,700-or-so women in federal prison, leaving out the more than 200,000 women in state and local prisons and jails. Women make up the fastest-growing segment of incarcerated people in the U.S., and about half are in jails, where people are held before their trials, after violating the terms of their parole, or after being sentenced to less than a year in lock-up. Between 1970 and 2014, the country saw a 14-fold increase of the population of women in jails, mostly for low-level drug offenses, loitering, and other crimes associated with broken-windows policing. More than 8 in 10 women in jail have survived sexual violence; nearly as many have experienced domestic abuse. About one-third of women in jail are living with severe mental illnesses, more than twice the rate of men in jail.

These troubling statistics point to what Sen. Booker, D-NJ, dubbed “a survivor-of-sexual-trauma to prisoner pipeline.” In a rousing address at Tuesday’s conference, Booker called on attendees to “get folk woke” on mass incarceration, the “biggest cancer of our body politic, the biggest shame of our national society.” Without proper diagnosis and treatment of the mental repercussions of trauma, advocates say, women who’ve been sexual assaulted or abused may self-medicate with drugs, leading to arrests on charges for possession or addiction-adjacent crimes like burglary and prostitution. In jail or prison, they’re often re-traumatized by searches, shackling, and abuse at the hands of guards or other inmates. And once they’re out, with a criminal record, they’ll struggle to find work and face limits on what kinds of government assistance they can receive.

Policymakers of both parties are looking for ways to break that cycle. Gov. Mary Fallin of Oklahoma, a conservative Republican, spoke to conference attendees on Tuesday about her efforts to reduce the state’s incarceration rate for women, which is more than twice the national average and higher than any other state’s. “For low-level, nonviolent offenses, there are alternatives that work better,” she said, to prevent crime and keep children out of foster care. Those alternatives include diversion programs that scrub felony charges from graduates’ records, reforms of policies that send released women back to jail for failure to pay fines, and more accessible substance-use treatment programs for pregnant women and mothers. On the federal level, Harris is working on a piece of legislation that would create competitive grants for states to devise pilot reforms of the cash bail system, which keeps people in jail for months or years before they’re ever convicted of a crime if they’re too poor to pay. In D.C., one of the few jurisdictions that don’t require arrestees to pay for pre-trial release, more than 90 percent of defendants are released without bail. Only 10 percent are arrested again before their trials, the vast majority for nonviolent offenses.

“We’ve been offered a false choice in criminal justice policy,” Harris said. “A choice that suggests one is either soft on crime or tough on crime, instead of asking are we smart on crime.”

Harris is optimistic that if the civil rights argument doesn’t resonate for fellow legislators, the fiscal one will. It cost about $32,000 a year to keep each U.S. inmate in federal prison locked up in 2015. In California, the annual cost per inmate is more than $75,000. One year of methadone treatment cost $4,700 in 2012. Studies have shown that the U.S. could save several billions of dollars by diverting drug offenders into treatment programs rather than prisons. “If we, like our friends in the private sector, are judging ourselves in government, unburdened by ideology, then this information forces us to … ask the question our friends in the private sector ask every day,” Harris said on Tuesday. “What is the ROI? What is the return on our investment? Because guys, as taxpayers, we are not getting a good return on our investment on this issue.”