Note: contains spoilers for Dream/Killer.
The force of nature that is Kathleen Zellner has been busy working towards Steven Avery's appeal and talking us through the reams of new evidence presented in Netflix's Making a Murderer Part 2, but you may be surprised to hear that this has not been her first brush with a true-crime documentary.
The defence attorney knows more than a thing or two about wrongful convictions, and she's got an ever-growing list of exonerations under her belt.
One of her success stories? Ryan Ferguson.
Dream/Killer, a true-crime film first released in 2015, documented his story.
If you thought the prosecution's case against Steven Avery was problematic, Ryan Ferguson was convicted of murder off the back of one phone call, and one person's dream-like memories.
In 2001, a man named Kent Heitholt was found dead in the car park of his place of work, the Columbia Daily Tribune. He had been strangled with his own belt. The murder went unsolved for two years, but a fresh lead appeared when police received an anonymous phone call implicating a local guy named Charles 'Chuck' Erickson.
On the night of the murder, Erickson had been to a number of Halloween parties and was high on drugs. He met his then-17-year-old friend Ryan Ferguson at around 10.30pm, but could not remember anything from the evening.
"I didn't know if it was memory, or if it was a dream. I assumed that if I'd done it, Ryan and I did it to get more money for drinks," Charles said of the crime.
During a police interview, footage of which was shown in the film, Erickson incriminated himself and his friend Ryan in the murder. Ferguson was later picked up by the FBI.
"I didn't do anything. I am innocent." Those were the words that Ryan kept repeating during his own police interrogation. He later added: "I'm innocent of even being there. I'm not involved in this, in any way."
One key piece of information relating to the crime was the tool used to strangle Heitholt. When questioned, Erickson could not name the belt – first he named "a shirt", and then later a "bungee cord", but it was the interrogator who revealed that the victim's "belt was ripped off".
Meanwhile, in Ferguson's interview, he was being told that his friend had knowledge of things that were never released to the press. "I don't know what the hell [Chuck is] talking about... I don't know if he's lying, I don't know if he was there," Ryan maintained, later adding: "I am telling the truth... There's nothing else I can say or do to prove my innocence."
It was soon announced in the press that the two arrests had been made, and State Prosecutor Kevin Crane then issued a statement revealing that Erickson was being charged with murder in the second degree, and Ferguson was being charged with murder in the first.
There was no physical evidence linking either one of them to the crime.
Almost two years later, a 20-year-old Ferguson was the first to stand trial.
Erickson was the prosecution's star witness, testifying that both he and Ryan had committed the murder. He talked of memories that had come to him since talking to the police. Two other witnesses were also welcomed to the stand: Shawna Ornt and Jerry Trump (the only people to have seen the perpetrators on the night of the crime).
It took the jury less than six hours to find Ryan Ferguson guilty of murder in the second degree and robbery in the first degree. He was sentenced to a total of 40 years.
Ryan's father Bill Ferguson was determined to prove his son's innocence. "We have just began the fight," he told reporters outside the courtroom.
Bill started to revisit the crime scene regularly. He collected paperwork from the case, reached out to witnesses and also launched a website to collect new information.
Shawna Ornt, the eyewitness, met with Bill and revealed that she had never been asked whether Ryan was the person she had witnessed on the night of the murder.
It came as a bit of a shock to hear Shawna claim that she'd told prosecutor Kevin Crane that she was "100%" sure that Ryan was not the person she had seen at the scene of the crime – a probable reason as to why she was not directly asked to identify Ryan in court.
"He [Crane] made me feel like I was the one that was in trouble and I was the one on trial," she said, implying that she had been intimidated before her appearance on the witness stand.
Bill continued his own amateur investigation, following new leads, and discovered other witnesses who undermined the prosecution's theory. This was presented at a 2008 evidentiary hearing by Ryan's new attorney, but the judge refused to grant a retrial and denied his appeal request.
"What did the judge say? The witnesses have no credibility," Bill explained. "As long as you're tethered to the motion court, there is no court house. You're never going to win that appeal, because they're protecting the verdict at any cost."
Enter Kathleen Zellner.
Having seen Ryan's original case play out on a TV programme, Zellner had made a note of the family name and decided, if contacted, she would take the case pro bono.
Sure enough, Bill emailed her and she called him back straight away. With the same tenacity that we've seen play out in Making a Murderer Part 2 in recent weeks, Zellner was certain of Ryan's innocence and adamant in her belief that she would get him out of prison.
New information soon came to light about the other witness, Jerry Trump, which called into question the validity of his original testimony. What's more, Zellner stated that there were seven unidentified fingerprints found at the scene, none of them Ferguson or Erickson's.
"It's so hard to undo these things," Kathleen said of the appeals process. "That's what I think is wrong. I think that's what needs to be changed." Zellner described how people in the judicial system had even tried to get her taken off the case.
During a new hearing, which would decide whether or not Ryan's conviction would be overturned, both Erickson and Trump retracted their original statements.
Allegations that Crane (the original trial prosecutor, who had since become a judge) may have knowingly allowed Trump to lie on the stand also surfaced, and he faced claims of 'fabricating evidence' during this hearing.
The defence lost this appeal, but that only spurred Zellner on further.
Ryan Ferguson's case then went to the oral argument (which you may recognise from Brendan Dassey's appeal process).
This time the ruling went in his favour and, in November 2013, Ferguson's conviction was vacated and he was released, having served 10 years in prison for a crime he did not commit. We now know that this happened just over two years before she took on the Avery case.
At the time, Zellner described the Ferguson case as being "disturbing on every level".
"You could not have a bigger failure, in the police investigation and the whole judicial system," Zellner said.
For true-crime fans, Dream/Killer (which is available to download from iTunes right now) is a must-watch. It also aired on Investigation Discovery in 2016.
