Salt Lake City, Utah (CNN) -- More than eight years after a homeless street preacher abducted and sexually assaulted her, a beaming Elizabeth Smart said that a federal jury's guilty verdicts Friday sent a message that victims can find justice.

"I hope that not only is this an example that justice can be served in America, but that it is possible that people can move on after something terrible has happened," she told reporters outside the Salt Lake City, Utah, courthouse Friday afternoon. "We can speak out, and we will be heard."

Smart testified for three days in the more than four-week trial of Brian David Mitchell, traveling to Utah from Paris, France, where she is on a mission with the Mormon church and set to return to next week.

Smart and her family, seated in the front row, were smiling -- while Mitchell, 57, was loudly singing "He died, the Great Redeemer died" -- as the jury announced it had found him guilty of kidnapping Smart in 2002 and transporting the then-14-year-old girl across state lines with the intent to engage in sexual activity.

Jurors deliberated for about five hours over two days before announcing the verdict.

In finding Mitchell guilty, jurors rejected the insanity defense mounted by his attorneys. Questions about his mental health had prompted law enforcement authorities to try him in federal, and not state court.

He faces a maximum sentence of life in prison when sentenced on May 25.

One juror, who asked not to be named, said "it wasn't an easy decision" to declare Mitchell guilty after an often emotional trial. Another juror said that the jurors "felt very, very comfortable that we had experienced the same thing and felt the same way" after a gut-wrenching trial.

"When you sit for hours at a time and listen to incredibly unreal things ... you've got to be pretty callous to walk away without having something tug at your heart," he said.

U.S. Attorney Carlie Christensen, whose office prosecuted the case, applauded the verdict, which she called "a long overdue and historic resolution of this case." She said that the trial hinged on Smart's precise testimony of the details of her captivity

"The beginning and end of this story is attributable to a woman with exceptional courage and exceptional determination," Christensen said.

Smart testified that she awoke to find a man holding a cold steel blade to her neck. She was taken from her bed and marched up a rugged mountain path in her red silk pajamas. When they reached Mitchell's remote camp, Smart testified she was "sealed" to her captor in a marriage ceremony, raped and shackled between two trees with a metal cable. She said she was degraded and treated "like an animal."

Smart said she was raped nearly every day during nine months in captivity and forced to drink alcohol, smoke cigarettes and watch Mitchell have sex with his legal wife, Wanda Barzee. She was forced to wear robes and a veil in public and was not permitted to speak to other people. She said she feared Mitchell would act on his threats to kill her and her family if she did.

"I felt that because of what he had done to me, I was marked," Smart testified. "I wasn't the same. My personal value had dropped. I was nothing. Another person could never love me," she added. "I felt like I had a burden the size of a mountain to carry around with me the rest of my life."

She said Mitchell told her their marriage was preordained and that she would be by his side as he took seven times seven wives and successfully battled the Antichrist. They would hold exalted positions in God's new kingdom, she was told.

A battle over a Mitchell's mental health played out during the month-long trial, with defense attorneys arguing that he was so mentally ill at the time he took Smart that he did not know it was wrong. Defense experts told the jury he was delusional and psychotic. One expert diagnosed him as a paranoid schizophrenic.

"An insanity defense is designed by Congress to be a very, very difficult thing to prove," assistant federal defender Robert Steele told the jurors. "I have to convince you by clear and convincing evidence there's a high probability that he has a severe mental illness. I have to convince you as a result he was not able to understand what he was doing, or what was wrong."

"If I've convinced you that God told him to kidnap, take another wife, take Elizabeth Smart, then he is not guilty by reason of insanity of kidnapping," Steele said during his closing argument. "If he believed he was commanded to go get more wives, that's part of the delusion, and that charge, too, is subject to the possibility of a not guilty by reason of insanity verdict."

Prosecutors portrayed Mitchell as a pedophile, narcissist and skillful manipulator who used fundamentalist religious dogma when it benefited him. Their experts said Mitchell could turn his religious beliefs on and off at will and talk his way out of trouble. Religious writings that might have seemed psychotic, including his manifesto, were actually cobbled together from other sources, one expert testified.

"The defendant's professed beliefs are highly consistent with fundamental extremists on what we might call the Mormon fringe -- the belief that polygamy needs to be restored," Assistant U.S. Attorney Diana Hagen said during her closing argument. "This is the environment that Brian David Mitchell became immersed in in the early 1990s.

"It provides a perfectly natural, non-psychotic explanation for why Brian David Mitchell behaves the way he does," she told the jurors. "There is no reason to resort to a mental health explanation in this case. The facts you have heard during this trial explain it all."

After the verdict was announced, Mitchell's step-daughter Rebecca Woodridge said she was dismayed by the verdict and concerned that Mitchell will be hurt in prison.

"I think he should have been found not guilty by reason of insanity and sent somewhere to be evaluated," she said.

As winter approached in late 2002, the trio journeyed from Utah to a homeless camp outside San Diego, California, where they spent several months. Mitchell was arrested after he tossed a brick through a church window and spent a week in jail. Back at the camp, Smart and Barzee grew so weak from hunger that they could barely stand up, Smart testified.

Mitchell gave a false name when he was arrested, and authorities released him without discovering his true identity.

The testimony revealed several encounters that could have exposed Smart's identity and perhaps brought her home months earlier had more questions been asked. Their robes and odd ways drew the attention of a police officer in the Salt Lake City Library, as well as others during their travels.

An officer testified that he asked to lift the young woman's veil, but the man refused, citing religious reasons. He did not press them further.

A woman who encountered them in California called the FBI, but the call wasn't followed up on, according to testimony. Another woman dubbed Mitchell "Osama bin Dairy Queen" and noticed the young woman with him seemed oddly withdrawn, but did not pursue it.

After Mitchell's arrest in California, Smart said she convinced him to return to Utah, saying the idea had come to her in a revelation. She said she knew her chances of being found would improve as she got closer to home.

Police stopped Smart, Mitchell and Barzee, on March 12, 2003, after a tipster spotted them outside a Wal-Mart in Sandy, Utah, just a few miles from Smart's home. At first, Smart testified, she was afraid to tell police who she was and gave officers a false name, as Mitchell had instructed.

Smart's demeanor on the witness stand was measured and matter-of-fact. The only time she displayed emotion was when she described being found by police and when she branded Mitchell a self-serving hypocrite.

Mitchell seemed preoccupied more with the pleasures of the flesh than matters of the spirit, she said, and used "revelations" and "blessings" to rationalize everything from sexual acts to smoking marijuana and reading Hustler magazine.

"He was crude, vulgar, self-serving. He was his number one priority, followed by sex, drugs and alcohol, but he used religion in all of those aspects to justify everything," Smart testified.

"Everything he did to me and my family was something I know God would never, would never ask somebody to do," Smart said pointedly. It was the only time the volume of her voice rose noticeably in court.

Mitchell's defense attorneys called a string of family members and friends, who described him as increasingly isolated and volatile as his religious zeal grew.

The defense case was marked by brief, dramatic moments in the courtroom.

Mitchell, who sang in court and was removed each day, fell to the floor with an apparent seizure while singing a Christmas carol. The following day, an upset Smart stormed from the courtroom when a witness testified about Mitchell's plans to have babies with her.

The defense ended its case with a psychologist who had diagnosed Mitchell as a paranoid schizophrenic, saying he suffers from "bizarre delusions." In his 2008 evaluation, Dr. Richart DeMier noted that Mitchell appears to have a family history of mental illness and was deemed "pre-psychotic" at 16 after exposing himself to an 8-year-old neighbor.

The prosecution countered with Dr. Michael Welner, who characterized Mitchell as a sadistic pedophile and a narcissist with a personality disorder. But, Welner said, he didn't have the "severe mental disease or defect" necessary for a successful insanity defense.

Mitchell's legal wife, Barzee, brokered a deal with state and federal prosecutors this year and was sentenced to 15 years in prison in exchange for testimony against her husband. But it was the defense, not the government that called Barzee to the witness stand.

The 64-year-old woman, an accomplished organist, described how the couple went from living in a Salt Lake City apartment and being active members of the Church of Jesus Christ of Latter Day Saints to a nomadic existence as the prophet "Immanuel" and his queen "Hephzibah" -- the Biblical names Mitchell chose for them.

She said she was crushed when her husband told her about a divine revelation that he should take plural "celestial wives" but complied with his instructions.

"We were given the commandment to take young girls, between the ages of 10 to 14 years old. We were to snatch them out of the world and train them in the ministries of God," testified Barzee, who is being treated for mental illness while serving her sentence in a Texas federal prison.

Barzee became emotional under cross-examination by prosecutor Felice Viti, conceding that her husband had taken advantage of her religious faith.

"He's a great manipulator," she said.

CNN's Ted Rowlands, Paul Vercammen, Jean Casarez and Ann O'Neill contributed to this story.