By LAUREN EFFRON and VICTORIA THOMPSON
After spending almost all of his 20s in prison for a murder he didn't commit, Ryan Ferguson is finally free.
"I didn't know this morning I would be standing here tonight. I didn't know anything. I didn't know the next step at all. It's very scary, and it's very daunting. I'm very glad to be here," Ferguson, 29, told a roomful of reporters, family and supporters at the Tiger Hotel in Columbia, Mo.
"I'm ready for anything," he said.
Ferguson said he didn't know he was going to be released from prison today. He thought his lawyers and parents were coming for a visit until he saw his lawyer, Kathleen Zellner, through the prison window. She was holding up a court booklet with the words "It Is OVER" written on the cover.
"It was a wild day for sure, a lot going on, a lot of emotions... I'm glad that the difficult part is over," Ferguson said.
A Missouri state appeals court panel last week overturned Ferguson's murder conviction, ruling that the prosecution withheld evidence from Ferguson's defense attorneys that could have perhaps exculpated him when he was on trial for the murder of Columbia Daily Tribune sports editor Kent Heitholt.
When Missouri Attorney General Chris Koster announced today that he would not retry or seek further legal action against Ferguson, the 29-year-old was allowed to leave prison once a Boone County judge signed off on the order. Ferguson, who has maintained his innocence while serving a 40-year sentence for the 2001 slaying of the newspaper editor, was released from custody around 6 p.m. today.
Before he was released, Ferguson said there was a tense moment when he had already changed into plain clothes, preparing to leave the maximum security prison where he had spent the past 10 years, when an officer told him he had to change back into an orange prison jumpsuit to be transferred to the Boone County Jail, where he had to wait for the judge's order.
"I've been so confused, the last couple of hours, they were hard," Ferguson said. "You don't know what's going to happen next, and it's incredibly scary. I was incredibly stressed out."
But then the judge's order came through, and Ferguson was a free man. He repeatedly thanked his supporters, his lawyers, friends and his parents, Bill and Leslie Ferguson, who were by his side during the news conference, for sticking by him through the ordeal.
"I would like to thank my parents ... without them I wouldn't have had any hope," Ferguson said. "As you can see, really, to get arrested and charged for a crime you didn't commit, it is incredibly easy and you can lose your life very fast, but to get out it takes an army."
One of the first things he said he wanted to do was eat Dairy Queen. Eventually, Ferguson said he was interested in advocating for criminals' rights and working with prisoners who claim they are falsely accused.
"Nightline" spoke to Ferguson in a jailhouse interview in October in which he talked about his decade-long saga that started when he was still in college.
In 2004, Ferguson was convicted of killing Heitholt in the parking lot of the Tribune on Halloween night 2001. None of the DNA collected at the scene -- the footprints and fingerprints -- matched Ryan Ferguson's, but the jury decided that testimony from Charles Erickson, one of Ferguson's classmates who claimed they'd murdered Heitholt together, and Jerry Trump, a janitor who identified Ferguson as one of the two men he saw in the parking lot immediately after the murder, was enough to convict him. Erickson was also convicted and sentenced to 25 years.
Five years after that 2004 conviction, Erickson met with Ferguson's attorneys to read a statement, which Ferguson's attorney, Kathleen Zellner, videotaped, admitting he had not been truthful in his testimony against Ferguson.
In April 2012, Ferguson was granted a new court hearing, where Erickson testified that he had lied about Ferguson's involvement in the murder during his initial trial. Then Trump, the janitor, took the stand and admitted that he, too, had lied at the trial. A convicted sex offender, Trump now claimed that police had pressured him to implicate Ferguson and Erickson from looking at a photo.
But at the time, Judge Daniel Green didn't believe Erickson's most recent account and found that there wasn't enough reliable new evidence to overturn his conviction.
Ferguson appealed Green's ruling, and this September, Ferguson's lawyers made arguments in the Western District appeals court, rebutting his conviction. That court overturned Ferguson's murder conviction last week.
Even today, Ferguson had no harsh words for Erickson, the man who was the driving force for his conviction, saying he, too, was an "innocent man in prison."
"I know he was used and manipulated, and I kind of feel sorry for the guy," Ferguson said. "He is not a killer, he does not belong in prison."
As for Kent Heitholt's family members, who are left to grapple with the sports editor's unsolved murder, Ferguson said, "I can't imagine how they're feeling, but the one thing is for them to look at all the facts and ask for justice."
"They've been lied to by people they trust and to see them misled by people that they believe are trying to help them. I can't imagine anything worse than that," Ferguson said. "I hope that everyone is able to ask that justice is done... and we can find who actually commited this crime."
ABC News' Dan Abrams contributed to this report