A woman who spat at a police officer while being arrested in a subway station last week wants to change the rules guiding rider conduct on public transportation, joining forces with a former Weather Underground radical to transform mass transit in Los Angeles.

“I witnessed a social injustice,” said Selena Lechuga, 22, at a press conference on Friday while seated next to Eric Mann, an organizer who has spent decades molding boisterous L.A. youth into revolutionary, defiant activists.

"I'm proud of what I've done and what I'm moving forward with, and with the movement that I will march on with," Lechuga went on to tell KNBC News.

A video that went viral on social media shows Lechuga harassing an LAPD sergeant for several minutes; then police take her into custody for interfering with an investigation involving a passenger that refused to remove her feet from a seat on a Metro train. Surrounded by activists affiliated with Mann’s Labor Community Strategy Center, Lechuga justified her actions, explaining she "stood up for a young Chicana" and accused the officer of being motivated by racism.

Under the guidance of Mann and her attorney, Lechuga would not address media inquiries about spitting at law enforcement.

"We're not answering that question," Mann told reporters.

Mann, who has been mobilizing anti-capitalist movements for nearly 50 years, was part of the militant Weather Underground Organization that formed in 1969. According to the FBI, the group was "inspired by communist ideologies."

Now allied with Lechuga, he is utilizing her widely-seen confrontation from last Monday to amplify his call for extreme reforms to L.A.'s mass transit system. Since 2014, Mann's group has led a “civil rights and climate justice” drive demanding Metro cut its police budget and eliminate fares for all passengers.

"We're asking you to support our campaign for free public transportation, to have no police on the trains and buses, to decriminalize fare evasion," Mann said as Lechuga nodded along by his side.

Mann claimed Metro's customer code of conduct criminalizes low-income passengers and people of color, suggesting the agency should eliminate all rules that dictate behavior for public transit riders.

"Let the code of conduct go," Mann told KNBC. “Just have a conductor — a decent human being — who could say very nicely, 'It would really mean a lot if you could just not do that.'"

Lechuga faces the possibility of misdemeanor prosecution, with a court date scheduled for February 16.

"I stand for what I have done in the sense that I am standing up for this movement," she said. "We need to defend ourselves in any way, shape or form."

Metro’s chief executive officer said he was “disappointed at the way the situation escalated,” but the agency will continue to enforce the code of conduct that Mann and Lechuga seek to abolish.

In December, the Strategy Center filed a lawsuit against Metro over records involving alleged racial injustices in policing the transit system.

Mann mentored and trained Patrisse Cullors, a co-founder of Black Lives Matter, who started organizing for the Strategy Center in 2000 at 17 years old. She has emerged as one of the most prominent organizers in Los Angeles, leading several movements targeting the criminal justice system.

Follow Jeffrey Cawood on Twitter @Near_Chaos.