By Eric Levenson and Eliott C. McLaughlin

CNN

NORRISTOWN, Pennsylvania (CNN) -- Bill Cosby arrived Monday at the Montgomery County Courthouse to face charges that he drugged and assaulted former Temple University employee Andrea Constand at his Cheltenham home in 2004.

With the streets outside the courthouse lined with television trucks, Cosby arrived arm-in-arm with Keshia Knight Pulliam, who played his television daughter, Rudy Huxtable, on "The Cosby Show." The courtroom was packed with members of the public and media.

District Judge Steven O'Neill instructed jurors that Cosby is innocent until proved guilty, opening statements are not evidence and Cosby has a right to remain silent.

"This is an important case, a weighty case, and there's a lot of evidence," he said.

The 79-year-old actor faces three counts of aggravated indecent assault. He has denied the accusations since 2005, when Constand first went to the police. Opening statements are expected to being Monday morning.

The district attorney at the time of the alleged assault declined to press charges, and in 2006 Cosby settled a civil suit with Constand that remained sealed for almost a decade.

Though more than 50 women have leveled allegations against the former "I Spy" star, the trial will focus on the testimony of Constand and only one other accuser, who has been identified as Jane Doe.

Ex-Playboy model Victoria Valentino, Florida nurse Therese Serignese and former actor Lili Bernard, all among Cosby's accusers, were spotted in the courtroom's overflow room. They are not expected to testify.

Those close to Andrea Constand say she is feeling strong and is ready to tell her side of the story. She has already traveled from Toronto to Pennsylvania, but it's not yet clear when prosecutors will call her to the stand.

"She knows she has the truth on her side," one source told CNN.

A he said, she said case?

Cosby's attorney, Martin Singer, has repeatedly denied the accusations against his client, at one point in 2014 decrying what he called "unsubstantiated, fantastical stories," which were becoming "increasingly ridiculous."

Prosecutors had sought to include testimony from 13 other accusers, but O'Neill ruled that would be too prejudicial.

Cosby has said he does not plan to testify. His deposition from the civil suit will stand as his explanation of what happened -- which means the trial likely will hinge on a classic case of "he said, she said."

In the deposition, Cosby said he had engaged in consensual sexual activity with Constand -- and that he had obtained Quaaludes in order to give them to women with whom he wanted to have sex. The unsealed deposition was central to Cosby's arrest in December 2015.

Cosby will face a jury of seven men and five women. Two jurors are black. The jurors will be sequestered in the criminal trial for about two weeks, the lawyers in the case have predicted.

The criminal complaint

In 2005, Constand, the director of operations for the women's basketball team at Temple at the time, told police she was drugged and assaulted by Cosby, a Temple alumnus who was 37 years her senior.

Sometime between mid-January and mid-February in 2004, Cosby invited Constand to his home in the Philadelphia suburbs to discuss her career plans. She told him she was "drained" and had been missing sleep, according to a criminal complaint.

Cosby told her to relax and gave her three blue pills, saying "these will make you feel good. The blue things will take the edge off," according to the complaint. She asked if the pills were herbal and he said they were. Cosby then offered her wine, and after some cajoling, she took a couple of sips, the complaint says.

She began experiencing blurred vision and difficulty speaking, lost all strength in her legs, and was "in and out," she told police. According to the complaint, Cosby positioned himself behind her on the sofa, penetrated her vagina with his fingers and put her hand on his penis. She told police she did not consent to the touching.

Constand woke up in the morning and discovered that her bra was undone, according to the complaint.

Mom confronts Cosby, complaint says

About a year later, Constand told her mother about the assault, and her mother spoke with Cosby, who acknowledged fondling Constand's breasts, penetrating her vagina and putting her hand on his penis, the complaint says.

In an interview with police, Cosby said that the pills he gave Constand were over-the-counter Benadryl. He described their sexual encounter as consensual, and he said she never told him to stop or mentioned that her senses were affected by the Benadryl.

Cosby also gave an unusual answer when asked if he ever had sexual intercourse with Constand: "Never asleep or awake," he said.

District Attorney Bruce Castor declined to press charges in 2005, citing insufficient evidence. Constand filed a civil suit against Cosby shortly after, and Cosby gave a deposition in that case. He and Constand settled the civil suit in 2006.

Cosby starred in "Fat Albert and the Cosby Kids" and "The Cosby Show." Through the latter he turned middle-class African-American family life into a groundbreaking TV sitcom.

His sweater-wearing portrayal of Dr. Cliff Huxtable made him a household name and one of the most beloved comedians in the world. In later years, Cosby became a public moralizer, speaking out against what he saw as the failings of African-American community in raising children.

CNN's Jean Casarez and Lawrence Crook III contributed to this report.