First in an occasional series.

The 40-year-old mother, bundled in a worn jacket, walks into the basement of the People's Emergency Center, hopeful that the past will finally fade away.

Tables are staffed by eager law students with laptops supervised by two lawyers. A fledgling volunteer group, the Philadelphia Criminal Record Expungement Project, C-REP for short, holds monthly clinics at the Powelton agency to help people who have been arrested but never convicted establish a clean slate. And, they hope, secure the lives their criminal records have held back.

The woman, Ms. Sanchez, who doesn't want her full name used, sits closest to ''the door, her round face warmed by dark curls and an easy smile. She has been out of work for almost two years, laid off as an assistant manager at a self-storage facility, and her unemployment compensation of $421 every two weeks ran out in July 2010. Her friend at Beloved St. John's church mentioned the expungement clinic.

"If I didn't have this criminal record," said Sanchez, who lives in Kensington, "I know I can get a good job. My resumé, I have good experiences." She also has a year at community college.

A law student puts Sanchez's name into the court database. Her record pops up.

On New Year's Day 1999, Sanchez defended her mother against Sanchez's drug-addicted brother. The police came, and Sanchez was charged with aggravated assault and related offenses.

Five months later, the commonwealth withdrew the charges. But Sanchez is serving time. She has applied for more than 40 jobs - at self-storage facilities, supermarkets, and retailers - but employer after employer told her she can't be hired because of her arrest more than a decade ago.

"Some said I couldn't get hired because I would deal with money," said Sanchez, "but I told them my issue has nothing to do with money."

Nationwide, one in four people has a criminal record, according to the National Employment Law Project. Pennsylvania law says employers are not allowed to consider applicants' non-conviction criminal history when hiring. But lawyers working with ex-offenders say such discrimination happens all the time. Non-conviction data can be expunged, but the remedy has its own roadblocks.

"It really follows you everywhere, and it destroys," Ryan Hancock, C-REP cofounder and board chair, said of criminal records. "If a person is not able to get a job, it destroys the family structure and produces more people who are dependent on state services. It's just a lose-lose situation."

Sanchez never thought her arrest would haunt her so. She has been a good worker.

"The system has a way of promising things," Sanchez said. "I am just hoping for the best."

The C-REP began a year ago with a street fair in West Philadelphia.

The four lawyers involved, said Hancock, 35, married with a toddler son, "were all looking for something to do, something we could have a large impact on."

The team, which now includes 28 law students, mostly from the University of Pennsylvania, has since held monthly clinics at the People's Emergency Center, and at a few churches where dozens have lined up.

"The community," Hancock said, "is telling us that it needs this work."

In many occupations, employers are required by federal or state law to reject candidates with certain convictions. Criminal history may also be considered in the issuance of professional licenses, such as those for barbers, nurses, and taxi drivers. But most employers have a great deal of discretion in hiring.

Yet a criminal history - of any type - proves to be a stumbling block.

One C-REP client in his 70s had been refused admittance to a nursing home because of his arrest in the 1970s in a fight. Another client had been arrested for shoplifting as a teen, a criminal record that more than a decade later kept her from a stable job as an adult.

"It's like stigma replaces common sense," said Sharon Dietrich, a managing attorney at Community Legal Services. "Once you have this thing on your record, people can just write you off."

Since it began, C-REP has conducted 23 community trainings, completed 327 client intakes, and filed 361 petitions in the Philadelphia Court of Common Pleas.

"We're not dealing with people with criminal ambitions," said Mike Lee, 28, C-REP's executive director and supervising lawyer. "These are people who want to recover their lives and start anew."

The filing-fee costs - $15 per expungement, and $12.50 per redaction - are paid through a Bread and Roses Foundation grant.

Recently, the Mayor's Office of Reintegration Services for Ex-Offenders contracted C-REP to work with its clients. Few nonprofits handle such work, and private lawyers charge up to $1,500, another hurdle.

"That the city can be helpful in taking down some of those barriers, we're excited," said William Hart, executive director of the Mayor's Office service. "It's just positioning our clients to get back into the real world in a meaningful way."

After intakes are completed, Hancock and cofounder Michael Hollander determine which applicants qualify for services. Those accepted are assigned a law student to draft petitions, which Lee reviews and files. Within two weeks, the court issues a hearing date. Lee argues the case, and encourages clients to attend to tell their stories. If the district attorney doesn't contest, the petition is granted without a hearing.

Many petitions are contested, Lee said, often based on multiple arrests. "Some people don't understand in certain neighborhoods how easy it is to be arrested."

Antwon Trapp, who visited the clinic last month, knows all too well.

Trapp, 25, a Frankford native and father of a 4-year-old son, drives for Paratransit and also works as an apprentice with the cement masons' union. But for a rough stretch, no one would hire him. At 18, Trapp was arrested for loitering; at 22 for drug possession; and at 23 for a DUI - incidents he blames on aggressive police. The commonwealth withdrew the charges in the first two cases, and Trapp was found not guilty in the third. But the case wound through the system for 15 months. Laid off, Trapp said the open case kept him unemployed.

He came to the clinic for "a clean slate. I just want to be clean."

C-REP has never lost a hearing in 173 cases. "It's partly due to the court understanding it's important," said Lee, a Drexel law school graduate, "and the case law supporting expungement for the societal good."

Once the expungement is granted, the court serves the official orders. C-REP sends a copy to the client, the Philadelphia Police Department, and the state police. When the expungement is complete, C-REP notifies the client and closes the file.

The process can take six months, if it runs smoothly.

"Expungement is supposed to clear up everything," Dietrich of Community Legal Services said, "but in practice it doesn't always work perfectly. It's like a game of whisper down the lane."

Criminal records can be cleared by one authority, but not others. And commercial background checkers "can be terrible about updating their records," Dietrich said. "Many have lost a job and don't know it."

"Sometimes you feel like giving up," Sanchez said. "I really want to work. I don't want to sit around the house. I want to work."

To make money, she has sold bottled water along Roosevelt Boulevard. She has tossed supermarket fliers on suburban lawns. She uses her old pickup truck to move and haul. Sometimes she sells what she finds in the trash.

Sanchez, who has a grown daughter, has cut back on most things, but she keeps the Internet to look for a job. She hopes to return to the self-storage business. "I'm just going through this dark moment," she said. "But it has to get better."

The C-REP clinic lasts about two hours that dreary Friday evening. Eleven people complete applications. Their cases are accepted. The room clears. As Hancock thanks the team for a solid effort, a man walks in gingerly, interrupting, with his baseball cap in hand. He wants to know whether he's too late, whether the expungement clinic is over.

One of the law students volunteers to stay.

Contact staff writer Kia Gregory at 215-854-2601, kgregory@phillynews.com, or @kiagregory on Twitter.com.