We've finally heard from Jay Wilds, the key witness in the murder of Hae Min Lee. And while the story he told the Intercept's Natasha Vargas-Cooper is more believable than the one he told the police or Adnan Syed's juries, it also makes Jay, as a witness, less credible — and thus it makes the case against Adnan much weaker.

If that paragraph doesn't make much sense to you, then you probably haven't been following Serial, the wildly successful podcast in which Sarah Koenig reopens and reinvestigates the 1999 Baltimore murder case that put Adnan, who was then 17 years old, behind bars for the rest of his life.

The case came down to the testimony of Jay, who claimed Adnan told him he was going to kill Hae, Adnan's former girlfriend. He claims Adnan strangled Hae, showed Jay the body and made Jay help bury Hae's body. Jay later led police to Hae's car.

There wasn't any physical evidence linking Adnan to the crime. There was only Jay's testimony — which seemed, at least in the prosecution's telling, to be backed up by cell phone records.

The problem is that Jay was, well, a bit of a liar. The details of his story changed on each telling. In one interview with police he tells them Adnan showed him Hae's body on Edmonson Avenue. In another interview with police he tells them it was at a Best Buy. A detective testifies Jay told him he first saw Hae's body on Franklintown Road.

Or take the murder itself. In one interview Jay tells police Hae was killed at the Best Buy. In another he says it was at Patapsco State Park. He tells a friend it was at the library.

The internet is thick with lists of Jay's lies (here's one, for instance). But Jay admits he's a liar. He tells the police he lied to them. He tells the jury he lied to the police. The prosecutors ask the jury to believe him anyway. And as Koenig puts it, "the spine" of Jay's story has never really changed. She quotes the prosecutor saying, "he tells police a consistent story about the defendant, he tells consistently the defendant’s involvement, the defendant’s actions on that day. He has never wavered on that point." Which is to say, Jay always said Adnan choked Hae to death and asked Jay to help him bury the body.

Koenig tried to interview Jay. She showed up on his doorstep one day and begged him to talk for her series. He refused. It was the great failing of Serial. In the end, the case wasn't about Adnan Syed, not really. It was about Jay Wilds — what he said, and whether it was true. And he wasn't talking.

Jay's interview with the Intercept

But Jay spoke to the Intercept's Natasha Vargas-Cooper. The story he tells her is, in some respects, more believable than the story he's ever told anyone else. But it also undermines the case against Adnan.

Jay gives Vargas-Cooper a simple reason for his lies: he was a serious drug dealer living in a culture that feared and mistrusted the police. Jay says:

It wasn’t just like I was selling a nickel bag here and there. At the time, this was Maryland in the ’90s, the drug laws were extremely serious. I saw the ATF and DEA take down guys in my neighborhood for selling much less than I was at the time. And they were getting sentenced to three and five years. I also ran the operation out of my grandmother’s house and that also put my family at risk. I had a lot more on the line than just a few bags of weed. The other thing to understand is something about the culture of Baltimore—this is where the ‘Stop Snitching’ video comes from. This is where it was produced. It went national, but it was produced in Baltimore. This is where people would have their house firebombed and still tell the police they knew nothing about it rather than to try to make some sense of what’s going on.

He also makes clear that his cooperation with the police was reluctant at best. Again, here's Jay:

I wasn’t openly willing to cooperate with the police. It wasn’t until they made it clear they weren’t interested in my ‘procurement’ of pot that I began to open up any. And then I would only give them information pertaining to my interaction with someone or where I was. They had to chase me around before they could corner me to talk to me, and there came a point where I was just sick of talking to them. And they wouldn’t stop interviewing me or questioning me. I wasn’t fully cooperating, so if they said, ‘Well, we have on phone records that you talked to Jenn.’ I’d say, ‘Nope, I didn’t talk to Jenn.’ Until Jenn told me that she talked with the cops and that it was ok if I did too. I stonewalled them that way. No — until they told me they weren’t trying to prosecute me for selling weed, or trying to get any of my friends in trouble. People had lives and were trying to get into college and stuff like that. Getting them in trouble for anything that they knew or that I had told them — I couldn’t have that.

Put this together and Jay's lies begin to make a bit more sense. He saw himself as a target. He feared the police. He feared implicating people he loved. He feared hurting his grandmother. He told the police enough to get them off his back, but he withheld anything he thought might widen their investigation to his friends and his family. Jay's actions here may not be right. But they're comprehensible, even familiar.

The problem is they completely undermine the state's case against Adnan.

Rabia Chaudry is a lawyer and national security fellow at the New America Foundation. But she's also a family friend of the Syeds, and she brought the case to Koenig's attention. And in the hours after Jay's interview broke, her Twitter feed was an almost unbroken celebration.

I spoke with Chaudry on Tuesday, and she explained why. Serial, she said, might be addicting entertainment for most people, but not for her. She's trying to free a loved one from serving a life sentence for a murder she believes, firmly, that he didn't commit.

Losing track of how many times Jay's story has changed. #FreeAdnan pic.twitter.com/4iCiYVHtFl — rabia chaudry (@rabiasquared) December 29, 2014

So yeah, i'm not sleeping tonight. My New Years just go SO HAPPY. #FreeAdnan #PerjuryFTW — rabia chaudry (@rabiasquared) December 29, 2014

"If what he’s reporting is the truth right now," she said, "then what he’s saying is that when he took the stand under oath at trial one, he lied, and when he took the stand under oath at trial two, he lied … If there was a third trial, that could be used to impeach his credibility."

Chaudry ticks off the changes. "Definitely the idea that the body was buried after midnight. The cell records were used again and again to show the phone was in Leakin Park at 7pm. Now [Jay] is saying it wasn’t 7pm. It was midnight. Jay is now saying at no point was he shown the body at Best Buy, that that never happened. He had this very detailed story of pulling into Best Buy; Adnan is wearing these red gloves. He's now saying, no, Adnan never told me he would do it that day, he just showed up and said I’ll be contacting you later."

The argument for trusting Jay has been that while the details of his story change, "the spine," as Koenig put it, holds. That's over, Chaudry says. "This completely destroys the state's case. This carefully planned out timeline with all the phone records is wrecked."

Jay's interview also undermines very specific charges. Adnan is away for life because the state used Jay's testimony to show premeditation — he said Adnan told him he was going to kill Hae before he did it. But in his interview with the Intercept, Jay doesn't seem to think the evidence for premeditation was beyond a reasonable doubt. "I don’t necessarily know if he meant to kill Hae before he did it or if it was a sudden moment thing," he says.

It's not about Adnan's innocence. It's about the state's case.

Listening to Serial, the hole for me has always been motive. Adnan's motive for killing Hae never made much sense. None of his friends thought he reacted particularly badly to the break-up. But nor was there good reason to disbelieve Jay. After all, Jay did know where Hae's car was, and while Adnan didn't have much reason to kill Hae, Jay had even less reason to kill her.

Chaudry doesn't buy it. She doesn't argue that Jay had reason to kill Hae, but she does argue he had reason to frame Adnan. "You have to remember Jay was a suspect in this case," she says. "Jay testified early on that the police said we’re considering charging you with this murder. The police came to Jay; he didn’t go looking for them. He had to give hair and blood samples. Why did he lie? Are you kidding me? He would’ve gone to jail for murder!"

Of course, Chaudry isn't a disinterested observer — a fact she freely admits. "I’m coming at this as someone who knew Adnan since he was young," she says. "If you imagine for a second someone you know and trust and love in your life and the story of someone like Jay is the only thing tying a person to the crime, do you believe that?" When I ask her for her theories of what could have happened that day, she says she doesn't know, but she offers three possibilities — Adnan murdering Hae doesn't even make the list.

I can't be as confident as Chaudry. I don't know Adnan, and I don't think Jay's lies prove Adnan's innocence. But they don't need to. It's guilt that has to be proven. And the burden of proof for a crime like this is extraordinarily high: beyond a reasonable doubt. Almost by definition, the testimony of someone who repeatedly lies to you is not beyond a reasonable doubt; it's testimony that you would be unreasonable not to doubt.

But that testimony — shifting and shot through with holes as it is — is all the prosecution had. Adnan is in jail for life because of the testimony of Jay, who lied to the cops, changed his story under oath, and is still changing his story even today.

Colin Miller, a law professor who writes at the EvidenceProf Blog, is unsparing in his evaluation of what this does to the state's case. "I said before that the prosecution's case was dead. With this interview, Jay has now burned the corpse."

Adnan has a petition into Maryland's Court of Special Appeals. Miller thinks his appeal has a real chance. But in terms of whether Adnan should be in jail right now, the question is whether his guilt is beyond a reasonable doubt. And it's hard to imagine, right now, how anyone could be free of doubt about Jay's testimony. "Even people who think maybe Adnan is guilty should conclude this shouldn’t have passed muster in a court of law," says Chaudry. And she's right.

Related: 7 addictive podcasts to listen to once you're done with Serial.