From WNYC in New York, this is NPR's On the Media.

I'm Bob Garfield.

And I'm Brooke Gladstone.

This week, a legal battle between the Cook County District Attorney's Office

and a group of journalism students at Medill Journalism School in Chicago made the news.

The issue is the student's investigation of the 1978 murder of a security guard named Donald

Lundahl, a crime for which Anthony McKinney has been serving a life sentence for more than 30 years.

The journalism students were part of the Innocence Project, a nonprofit that aims to free

wrongfully convicted people around the country.

With their professor, David Protests, the class conducted a three-year investigation during which

two eyewitnesses, whose testimony sent McKinney to prison, recanted. Dennis Pettis was one of those

eyewitnesses.

He told the students that 30 years ago, the police had abused and intimidated him

into lying about witnessing the murder.

What did they tell you to say happen?

That incidentally killed.

And you signed a statement at the time to attest for this.

And was that true at the time? No.

So you're saying today that what you wrote or said at that time was not true?

That's correct. Okay.

The students compiled other documents, including sworn affidavits that attested to McKinney's innocence.

They turned their findings over to lawyers in 2006,

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