Johnny Williams spent 14 years in prison for an attempted rape he never committed. On Friday, a judge overturned his conviction. And on Tuesday, the 37-year-old Williams spoke publicly for the first time.

"I'm truly happy," Williams said in a one-on-one interview at Santa Clara University. That's where a team of students and lawyers from the Northern California Innocence Project helped prove that the DNA on a 9-year-old's T-shirt did not belong to him. The DNA is what led to his 1998 attempted rape arrest.

"Everything happens for a reason," he said.

This is the second innocent person the Innocence Project has exonerated this year, and its 16th victory since its creation in 2001. The class at Santa Clara University also helped free Ronald Ross, 51, who was convicted in 2006 for an attempted murder and was released at the end of February, when the judge dismissed the case.

Williams, born and raised in Oakland, has a different twist to his story.

He served his entire 14 years and was released from prison in January. So, when Alameda County Superior Court Judge Larry Goodman wiped his record clean, he had already served out his whole punishment -- the last stretch at Richard J. Donovan Correctional Facility in San Diego -- one that began when he was 23 years old.

Before this, he had no criminal record.

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But Williams on Tuesday did say that his life had been heading in the wrong direction before his arrest. He said he never graduated high school and never finished college. Being behind bars for most of his adult life made him realize he now has a second chance.

"I want to learn from my past experiences," Williams said, not wanting to elaborate on his past life in Oakland. "I'm just happy to be back on the streets. I'm trying my best to get a job and go to school."

As for the Oakland police who arrested him, Williams only had this to say: "We all make mistakes."

On Sept, 28, 1998, a man who called himself "Johnny" sexually accosted a 9-year-old girl as she walked home from school. The next day, while walking in the same area, the same man attempted to rape her. Williams was a former neighbor of the girl and familiar with her family. When the girl first reported the assault she did not say she knew the attacker, which suggested a stranger.

However, people who knew the girl suggested to police that "Johnny" may be Williams, according to Santa Clara University's Innocence Project. One week after the attack, Oakland police collected the clothes the girl was wearing during the assault. Forensic tests at the time of trial were unable to confirm biological evidence and no DNA testing was performed. On June 8, 2000, Williams was convicted of two counts of forcible lewd conduct against a child and one count of attempted rape.

Williams wrote the Innocence Project a letter, and the students took up his case along with their sister organization, the California DNA Project. Working with the Alameda County District Attorney's Office, the T-shirt was retested and Williams' DNA was excluded.

The Innocence Project's supervising attorney Maitreya Badami said years were taken off Williams' life, but he is eligible for a significant sum of money. All eligible, exonerated prisoners can earn up to $100 a day for every day they wrongly spent in prison. Badami said that could be about $500,000, and even though it may take a long time to get it, Williams is definitely a candidate for that money.