She jumped over a crowd barrier outside the courthouse and yelled "Women's lives matter" before being wrestled to the ground by courthouse deputies about 10 yards in front of Cosby as he walked toward the building's front doors.
She later said she didn't have any bad experiences with Cosby on the show, but wanted to make him "uncomfortable" as he had done to so many women.
"I want to turn again to the defendant's words", DA Kevin Steele said in Montgomery County Court, where Cosby faces trial for allegedly assaulting Constand in his suburban Philadelphia mansion in January 2004.
Defense attorneys, who are scheduled to present their opening statement on Tuesday, had attempted Monday to have one member of the jury removed because a prospective juror who was not chosen said he'd told her that he believed Cosby was guilty.
This time, O'Neill has warned the trial may last a month.
In long, at times rambling remarks kicking off perhaps the most high-profile case of his career, Steele rehashed the details of the "he-said, she-said" case, saying that it was about broken trust.
Yet the three counts of aggravated indecent assault in connection with Constand, who now lives in Canada, are the only criminal charges to stick against Cosby.
Ms Rochelle was charged with disorderly conduct and could be fined if convicted.
Cosby seemed startled by the commotion as a half-dozen protesters chanted at him. "I have three friends for you that will make you relax".
The first trial, in June 2017, ended when the jury failed to reach a verdict.
Rochelle, a 38-year-old singer and actress, spoke to Inside Edition exclusively, right after she was released from custody. The entertainer, now 80, has denied each the accusations, stating any sensual encounters he may have had have been consensual.
The #MeToo movement is proving an important factor in this case, with jurors asked during selection how much they knew about the campaign and whether it would affect their decision-making.
Constand filed a police report in 2005, but Cosby was not charged at the time.
Ms Constand, who is from Canada, had played basketball professionally in Italy and for Canada's national women's team. Judge Steven T. O'Neill interviewed the seven men and five women on the jury, as well as six alternates, after bias concerns were raised by the defense.
The Bill Cosby sexual assault retrial has drawn a lot of media attention as of late. Then Cosby was back on his way to meet the men and women who will decide his fate. The two sides agreed at the first trial not to mention the lawsuit.