Every Sunday at 6 p.m., Karen Garrison hosts a radio show in her home in Washington. Her twin sons were convicted as members of a crack cocaine conspiracy, a charge they deny, and received long sentences under mandatory sentencing guidelines. (Marvin Joseph/The Washington Post)

The first time someone called Karen Garrison an activist, she looked up the definition to see if it fit.

“I never thought of it like that,” she said. “I just thought it’s what mothers do.”

A mother, she thought, would fight back if her sons were sent to prison for more than a decade, found guilty of conspiracy to distribute cocaine and crack cocaine without prior records and without physical evidence linking them to any crime.

Over the past 20 years, the high school-educated cosmetologist has transformed herself into both an advocate for reform of, and a sympathetic guide to, the labyrinthine criminal justice system.

Now 59, she works by day for a D.C.-based nonprofit group that fights laws dating back to the 1980s mandating long mandatory minimum sentences for certain crimes, particularly drug offenses involving cocaine and crack cocaine that she and other activists say have been applied disproportionately to African Americans.

By night, she runs an online radio show from her dining-room table, covered with legal briefs and letters from prison.

“She couldn’t just let them take us away and throw away the keys. She had to reinvent herself,” said Lamont Garrison, one of her twin sons who was arrested with his brother Lawrence in 1998 and incarcerated soon after. “Necessity is the mother of invention.”

Until Lamont and Lawrence went to prison that year, Garrison hadn’t cared much about politics. She was doing hair and selling some crafts on the side — homemade place mats, necklaces.

What she cared about was getting her twin sons on a path toward a good life. She raised them as a single mother in the D.C. neighborhood of Trinidad, living through the crime wave that helped lead to the federal mandatory minimums.

Her sons were altar boys. In the spring of 1998, the twins were about to graduate from Howard University with degrees in political science and plans to go to law school and practice together.

Then the U.S. marshals came to their door. A confessed drug dealer they knew through his auto-repair business had implicated them in a vast multi-state conspiracy involving 10 kilos of cocaine and 500 grams of crack, claims the Garrisons denied.

No drugs were found on them or in their home, nor was any drug money uncovered. They had no prior criminal records.

But they were convicted after a four-day trial in 1998. Lawrence was eventually sentenced to a mandatory minimum sentence of 15 ½ years; Lamont received a mandatory minimum sentence of 19 ½ years.

When their mother started loudly protesting, she found that “nobody cared whether they were innocent or guilty, they just knew that the sentence was too much — it was too much time.”

In pleading guilty, the drug dealer who fingered the brothers had ample reason to do so. Tough drug laws passed in the 1980s meant that one of the only ways out of a long sentence was to provide “substantial assistance” to the government in prosecuting another offender.

With a crack epidemic raging, Congress had created mandatory minimums for drug cases, with one gram of crack cocaine the equivalent of 100 grams of powder cocaine for the purposes of sentencing.

The amount of both crack and powder cocaine involved in the Garrisons’ case meant that, according to federal sentencing guidelines and mandatory minimums, the brothers faced prison sentences of at least 188 months, or about 15 ½ years.

There was a “safety valve” provision added to the law in 1994 that gave first-time offenders like the Garrisons a chance to avoid harsh mandatory sentences for nonviolent drug crimes. But qualifying required giving what the government considered complete and truthful information.

All but two of the other co-conspirators in the case pleaded guilty, but the Garrisons — maintaining their innocence throughout — insisted on going to trial. When the verdict convicting her sons was read, Karen Garrison fainted on the courtroom floor.

Under the sentencing guidelines, Lamont got an extra four years — 19 ½ instead of 15 ½ — for testifying in his own defense.

Karen Garrison put together a packet of information about her sons and began shopping it to the media.

“Once I was on the news, it was a breakthrough, but it wasn’t a solution,” she said.

She soon learned of Families Against Mandatory Minimums and attended her first meeting at Christ Church on Capitol Hill in 1999.

“When it came time for Karen to tell her story, she was kind of quiet,” said Monica Pratt Raffanel, FAMM’s spokeswoman. “It’s hard to imagine that with her, because she has such a big personality, but families struggle a lot with just the feelings of shame and isolation and not knowing if anybody’s going to understand.”

But Garrison spoke out. And she told her story again and again, at more meetings with more organizations — the Sentencing Project, Open Society Institute, Justice Policy Alliance.

She credits Angelyn Frazer, a former FAMM staffer who now works at the National Association of Criminal Defense Lawyers, with helping her figure out which meetings to go to, how to navigate the legislative process, how to lobby members of Congress. She built a big display board covered with photographs of herself and her sons and took it to conferences across the country.

Garrison started volunteering at FAMM. In 2003, she started working there part time. Soon she became a full-time staff member. The bubbly personality she honed as a traveling makeup artist, combined with the no-nonsense attitude that helped her raise twin boys, powered her push for legal reform.

“She was so clearly committed to understanding sentencing as much as she could, and to fighting for her sons’ freedom or some sense of justice in her sons’ case, that I was impressed with that level of drive,” said FAMM President Julie Stewart, a former staffer at the libertarian Cato Institute who founded the nonprofit after her brother spent five years in prison on marijuana charges.

“She wasn’t going to roll over,” Stewart said of Garrison. “She was going to fight.”

But Garrison’s sons remained in prison.

She found over the years that people didn’t know as much about the criminal justice system as she thought they would. So she started her own online radio show to spread the word. She dubbed herself the “Mommie Activist.”

In her Sunday night online broadcasts, she covered everything from “snitching” to updates on marijuana legalization, creating an alternative map of the criminal justice system, pointing out what she considers traps and flaws. On Thursdays, she held weekly prayer calls.

Changes were long in coming. Finally, in 2005, the Supreme Court ruled that federal judges need no longer be bound by mandatory sentencing guidelines.

In 2007, a modest amendment to the federal sentencing guidelines for crack allowed Lawrence to shave 36 months off his sentence, and Lamont 48.

A more substantial reduction came in 2010, when Congress passed the Fair Sentencing Act, which moved toward equalizing sentences for people convicted of crack-cocaine offenses, who most often are black, and people convicted of offenses relating to powder-cocaine offenses, who tend to be white.

By then, Lawrence was home and Lamont was on his way.

There is little hope among Garrison and other activists for another reduction in the gap between crack and cocaine sentencing. But they are hoping to make the Fair Sentencing Act retroactive and to broaden the safety valve.

Prison reform has begun to attract interest on the right, thanks to an alliance of libertarians and social conservatives. Sen. Rand Paul (R-Ky.) has teamed with Sen. Patrick J. Leahy (D-Vt.) on new safety-valve legislation that would give judges greater flexibility in giving prison terms below the sentencing guidelines.

Garrison has kept fighting.

“You sort of wonder how involved a person will stay, because it’s not uncommon for folks to have their loved ones come home and just want to get back to normal life, whatever that is,” said Pratt Raffanel. “But Karen, that just wasn’t her course. She’s as dedicated now as she’s ever been.”

This past Christmas, Garrison nearly collapsed again. She had both her sons back home. Lamont has found work as a personal trainer at a Virginia gym, and Lawrence does hospital billing. She prepared a giant feast — black-bean patties, turkey salad, macaroni and cheese, cornbread, asparagus, hash-brown quiche, sweet potato pie, cheesecake.

When it was done, she was ready to slip under the table and go to sleep.

“It was the first Christmas of the rest of my life,” she said. “A good life.”