SAN FRANCISCO (CBS SF) — Less than four weeks after the violent murder of 18-year-old BART rider Nia Wilson at Oakland’s MacArthur station, attorneys representing her family have filed a claim against the transit agency charging that her death was preventable.

According to the claim, BART failed to take action when the suspect, John Cowell, is believed to have jumped a BART turnstile to avoid paying a fare and that the agency should have known he was a threat because two other riders complained about his behavior in the days prior to Wilson’s death.

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John Cowell was arrested while riding a BART train a day after allegedly slashing Wilson’s throat on the MacArthur station platform on July 22 around 9:35 p.m. Cowell also stabbed her sister Letifah Wilson, 26, in her neck as another sister, Tashiya Wilson, 21, watched in horror.

Cowell has been charged with murder for allegedly killing Nia Wilson and with premeditated attempted murder for the alleged attack on Letifah Wilson.

At his San Francisco office Friday morning, accompanied by Wilson’s sisters and her parents, attorney Robert Arns said, “What the family wants to do with this lawsuit, one of the main things, is make BART safe for everyone.”

“Nia, in her short life at age 18, she wanted to save lives,” he said, adding that she dreamed of becoming a medical technician and joining the U.S. Navy.

“Nia’s death is not some horrific anomaly that occurred in two seconds and that nobody could do anything about,” Arns said. “There’s a serious and endemic public safety problem on BART and just about everybody who rides BART knows that.”

According to the claim, BART has failed to stop people sneaking onto the system without paying.

Arns said his attorneys plan to prove a link between fare-evasion and crime on public transportation, adding that public records show more than 22,000 people ride BART illegally on a daily basis.

Arns said Cowell had been cited for fare-evasion on BART at least once before.

In addition, Arns said two different people have contacted his law firm since Nia Wilson’s murder, claiming that Cowell had threatened them on BART in the days before the July 22 killing.

One 72-year-old woman said that, as she was leaving San Francisco’s Civic Center station, Cowell accosted her. She said he made a slashing movement across his neck in a threatening manner when she told him “I’m not afraid of you,”

The woman then went to report the threat to the station agent but couldn’t find one and ultimately did not report it, Arns said.

Another person told Arns they also encountered Cowell at the MacArthur station and noticed he had a knife. That person also tried to report it to the station agent but ultimately couldn’t find one.

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“If BART stopped criminal fare evaders, Nia would be alive,” Arns said. “What is the standard for BART? That they must use the highest care to protect passengers from assault.”

The claim is seeking that BART institute a program called the Nia Wilson Crime Statistics Notice, displaying crime data for the last four years at each BART station, including in the parking lots, platforms and on cars.

It’s also seeking to force BART to implement safety measures and staffing policies to prevent fare-evasion and criminal activity at all BART stations.

The claim was filed Friday with BART as a public entity claim because the transit agency is a public entity. BART must respond to the claim within six months, attorney Jonathan Davis said.

If the claim moves forward, a lawsuit will then be filed in Alameda County Superior Court, according to Davis.

Wilson was one of three people who died on the BART system in a five-day period in late July.

In statement in released earlier this month in anticipation of the claim, BART spokeswoman Alicia Trost said, “Nothing is more important than the safety of our riders and employees.”

Trost continued, “In the last several years BART has launched a multi-prong approach to reduce fare-evasion, including a new proof-of-payment ordinance and inspection teams as well as infrastructure changes to make it harder to bypass fare gates.”

Trost said BART has also installed working cameras on all train cars and has “a robust network of more than 4,000 surveillance cameras.”

Additionally, she said BART has increased patrols using overtime since the spring of 2017 and has “worked tirelessly” to fill officer vacancies.

“Arrests surged last year by nearly 40 percent due to the fact our officers were in the right place at the right time,” she said.

“The murder of Nia Wilson on BART is a tragedy and we continue to extend our deepest condolences to the Wilson family. We are thankful the suspect is in custody due in large part to our surveillance system,” Trost said.

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