What did she know, when did she know it, and how could she not know? Six years after the Boston Marathon bombings, questions remain surrounding the role of Katherine Russell as a potential accomplice to the deadly crimes committed by Islamic extremists Tamerlan and Dzhokhar Tsarnaev.

Katherine Russell (who sometimes went by her married name, Karima Tsarnaev) has never been charged in connection with the 2013 Boston Marathon Bombing terrorist attacks, which killed three, resulted in 17 amputees, and wounded another 240 innocent people.

While the two perpetrators of the attacks have been brought to justice (with Tamerlan’s death and Dzhokhar currently locked up in a supermax prison), Russell has somehow escaped justice for potentially being an accomplice to a vicious Islamic terror attack on U.S. soil.

She who was born to a “tight-knit” Catholic family in Rhode Island, had excelled in school and enrolled in Suffolk University. Affectionately known to her friends simply as Katie, Russell was described as a popular, friendly person who had everything going for her.

Her life took a radical turn for the worst in 2009 after meeting Tamerlan Tsarnaev, a devout Muslim who would watch radical Islamic videos and generally hated what the United States stands for, according to a neighbor.

Russell converted to Islam in 2010 at the Masjid al Qur’aan in Boston. Later that year, she dropped out of college. She was rarely seen outside of the apartment (other than making her trips to and from work as a home health care assistant) she shared with her husband and young child, according to neighbors. This means that she was almost certainly present as her husband used their apartment (which was smaller than 800 square feet) to make pressure cooker bombs and watch radical jihadi videos.

Her defense team has framed her relationship with Tamerlan as an abusive one. They claim she worked tirelessly, and spent the rest of her time caring for their child and isolated from even the people inside her small home. They say she had no advanced knowledge of his plans.

However, there is more than just circumstantial evidence tying Russell to the terrorist act.

Months before the bombing, she conducted online searches on her Macbook computer for “wife of mujahedeen” and “If your husband becomes a Shahid, what are the rewards for you?” prosecutors said during the 2015 trial. Mujahedeen means people engaged in jihad, or Islamic holy war. A Shahid is a martyr for the religion of Islam.

Following the attacks, she seemed to justify the ruthless methods of her husband and brother-in-law, texting a friend: “Although a lot more people are killed every day in Syria and other places. Innocent people.”

She also retained radical Islamic propaganda videos on her personal computer, such as al Qaeda’s infamous “Make a Bomb in the Kitchen of Your Mom” video that has provided bomb-making guidance for countless jihadis.

After the bombing, police sought out the help of the local Boston community to help find the suspects they had identified through grainy photos. When pictures of Tamerlan’s face had started to appear on television, Russell called him to inform him, according to police sources, who told The Weekly Standard at the time.

Russell was profiled as someone who was well aware of the planning stages of the attacks in the movie “Patriots Day,” the 2016 film about the Boston Marathon bombings. Her lawyers insist that it unfairly portrays their client, while the filmmakers stand by their research related to her role in the attack.

Since the terror attacks, Russell has jumped around from state to state. She first attempted to move back into her family home in Rhode Island. Although there were signs of initial reconciliation, the efforts to bring her back into the fold failed after she clashed with her family over her Islamic faith, according to one relative.

She found a better fit in the New Jersey home of her late husband’s sisters, Bella and Ailina Tsarnaev, the latter who appears to be a radical Islamist. In 2015, she told her boyfriend’s ex-girlfriend that she knew people who could set off a bomb in her home.

Russell has since remarried and had another baby, Ailina Tsarnaev said.

It remains unclear whether prosecutors will ever decide to pursue charges against Russell. She has kept an extremely low profile over the past year. In September 2016, authorities wanted to question her with regard to Tamerlan Tsarnaev’s activities. Russell released a statement through her lawyers in September 2016.

“The injuries and loss of life – to people who came to celebrate a race and a holiday – has caused profound distress and sorrow to Katie and her family. The reports of involvement by her husband and brother-in-law came as an absolute shock to them all,” the statement said. (For more from the author of “Boston Marathon Bombing, 6 Years Later: Did Jihadi Wife Katherine Russell Escape Justice?” please click HERE)

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