The Prosecutor Who Stared Down Bill Cosby

If cameras had been present, it would have been a viral moment.

Partway through her closing argument on Tuesday, Kristen Gibbons Feden, a 35-year-old prosecutor, strode across the courtroom and stared down Bill Cosby from a few feet away. Fighting off the defense’s attempts to paint Mr. Cosby’s main accuser as a “con artist,” Ms. Feden told the packed house that the real con artist was “the man sitting right there.”

At another point, Ms. Feden saw what she thought was a smile spreading across Mr. Cosby’s face. “He’s laughing like it’s funny!” she said, a shot that later prompted Mr. Cosby’s team to dispute that he had laughed.

And she lit into Kathleen Bliss, one of Mr. Cosby’s lawyers, who had attacked some of the women who testified against him as promiscuous party girls out for cheap fame and a payday.

“She’s the exact reason why victims, women and men, of sexual assault don’t report these crimes,” Ms. Feden said.

Her starkly confrontational closing sent a jolt through the courtroom, as a young lawyer known locally as a rising star dramatically seized the moment in the first high-profile sexual assault trial of the #MeToo era.

Ms. Feden, the veteran of many sex crime trials in Montgomery County outside Philadelphia, is a dogged preparer. But her closing words, she said on Friday, sprang as much from her basic human reaction as from courtroom experience.

“I’m a very loud person, and I don’t like seeing people get picked on,” she said in her first interview since the jury returned a guilty verdict. “I’m also a very emotional person. That can be a flaw, but it can also be used as a tool.”

Ms. Feden’s role in the closing argument, which she shared with another prosecutor, M. Stewart Ryan, was a surprise to some close followers of the case, who had expected Kevin R. Steele, the Montgomery County district attorney, to handle it, as he had in Mr. Cosby’s first trial last year, which ended in a jury deadlock.

But her effectiveness was no surprise to those who have watched her in action over the years.

“She’s very bubbly and nice, the kind of person who would come up to you and hug you, but in the courtroom, she becomes a very fiery, aggressive lawyer,” said Judge Garrett D. Page of Montgomery County Court of Common Pleas, who once had Ms. Feden as a clerk and later presided over cases argued by her.

“She can go right from her script and do things that will really have an effect on the jury,” he said. “She’s flowing with the traffic.”

Ms. Feden grew up in Willingboro, N.J., across the Delaware River from Philadelphia. Her father was a physician, her mother a speech pathologist.

She attended Lafayette College in Easton, Pa., where she majored in neuroscience. She thought she would become a doctor, until her older sister, who was in medical school, pointed out that she didn’t like bugs or blood.

But she had always been a huge fan of “Law and Order: SVU.” “Everyone knew not to bother me when it was on,” she said.

After two years as a financial analyst at Bloomberg in New York, she enrolled in law school at Temple University, where she was an editor on the Temple Political and Civil Rights Law Review.

She joined the Montgomery County district attorney’s office in 2012, and soon began working on sex crimes and elder abuse cases. She recalled the first sex crime case she prosecuted alone, a juvenile case involving a defendant accused of raping his cousin repeatedly over many years.

She lost the case. “It was devastating for everyone involved,” she said. But it also taught her the value of helping accusers confront defendants in court, whatever the outcome.

“One thing I stress is that a conviction is not necessarily going to change anything,” she said. “But it may make you feel that much better that you can look someone right in the eye and say, ‘You did this to me.’ ”

In a news conference following the verdict on Thursday, Mr. Steele, the district attorney, credited Ms. Feden with helping spearhead the effort to prosecute the case after a previous district attorney had declined to do so. “She was adamant, adamant about what to do,” he said.

It was Ms. Feden who traveled to Toronto with a group of detectives in August 2015 to meet with Andrea Constand, the former Temple University employee who accused Mr. Cosby of drugging and sexually assaulting her. (Ms. Feden recalled the date easily, she said, “because I had to miss my sister’s birthday.”)

After Mr. Cosby’s first trial, Ms. Feden, who is married to another lawyer and has two young sons, took a job at the Philadelphia law firm Stradley Ronon. Bill Sasso, the firm’s chairman, had personally called to recruit her after seeing her on the cover of Philadelphia Business Journal, which had named her one of its “40 Under 40.”

Ms. Feden took a leave from the firm to serve as a special prosecutor for Mr. Cosby’s retrial. She handled some of the testimony, including Ms. Constand’s, then took on the responsibility of helping sum up the prosecution’s case for the jury.

Some news reports described the jury wincing as the defense, in its own summation, attacked Ms. Constand and other women who testified against Mr. Cosby as being motivated by “money, press conferences, TV shows, salacious coverage, ratings.”

Ms. Feden had already outlined what she was going to say during her turn, but after hearing the remarks by Ms. Bliss, the defense lawyer, she began scribbling additional notes.

“What I tried to do was contrast her character assassination with these very humane, very human emotions that had been flowing from the witness box,” she said.

Andrew Wyatt, a spokesman for the defense, declined to comment Friday on Ms. Feden’s riposte to Ms. Bliss. In court, Ms. Bliss had said that sexual assault is a “worldwide problem” but that “questioning an accuser is not shaming a victim.”

Ms. Feden said in the interview that she had been stunned when she spotted Mr. Cosby’s smile. “I’m thinking, ‘Are you kidding me?’ ” she said.

It was a fleeting moment, but one significant enough that Mr. Wyatt publicly rebutted her claim that Mr. Cosby had laughed, and suggested that she was trying to distract the jury from what he called a weak case.

Asked about the impact of the guilty verdict, Ms. Feden said she hoped it would educate people about the courage it still takes women to come forward.

“As much as people like to judge and blame the victims,” she said, “the victim is already judging and blaming herself.”