CHILTON, Wis. — A man who spent 18 years in prison for a rape he didn’t commit was convicted yesterday of murdering a photographer, whose charred bones were found in a burn pit outside his home.

Steven Avery, 44, faces a mandatory life prison term for killing Teresa Halbach, 25, on Halloween 2005 near his family’s salvage yard.

The jury convicted Avery of first-degree intentional homicide and being a felon in possession of a firearm. He was acquitted of mutilating a corpse. The panel deliberated over three days and heard a month of testimony.

Halbach disappeared October 31, 2005, after going to the salvage yard in rural Manitowoc County to photograph a minivan that Avery’s sister had for sale through Auto Trader Magazine. Avery called that morning to request the photo, testimony showed.

A few days later, Halbach’s vehicle was found in the Avery salvage lot under branches, pieces of wood, and car parts. Investigators then spent a week on the 40-acre property and found charred fragments of her bones in a pit behind Avery’s garage and in a barrel, along with her camera and cell phone.

Avery’s nephew Brendan Dassey is due for trial next month. In March 2006, he confessed to helping kill and rape Halbach.

Prosecutors then added charges of sexual assault, kidnapping, and false imprisonment to Avery’s case. But Mr. Dassey recanted his confession and rejected a plea deal that would have required him to testify against his uncle.

Two years before Halbach died, Avery was released from prison after serving 18 years for a Manitowoc County rape that DNA analysis showed he did not commit. He later settled a wrongful-conviction lawsuit against the county for $400,000 and used it for his defense.