Wisconsin Attorney General Appeals Brendan Dassey's Overturned Conviction

"We are disappointed," said the lawyer for the "Making a Murderer" subject.

— -- The Wisconsin Attorney General has appealed last month's ruling that overturned the conviction of Brendan Dassey in the murder of photographer Teresa Halbach.

According to documents obtained by ABC News, earlier today, Brad Schimel filed the appeal to the 7th U.S. Circuit Court of Appeals on behalf of Warden Michael Dittmann and the State of Wisconsin.

A press release from Schimel's office stated that Halbach's family "fully supports the state's decision to seek justice on behalf of their daughter."

“We believe the magistrate judge’s decision that Brendan Dassey’s confession was coerced by investigators, and that no reasonable court could have concluded otherwise, is wrong on the facts and wrong on the law,” Schimel said in a statement. “Two state courts carefully examined the evidence and properly concluded that Brendan Dassey’s confession to sexually assaulting and murdering Teresa Halbach with his uncle, Steven Avery, was voluntary, and the investigators did not use constitutionally impermissible tactics.”

After viewing footage of Dassey's confession in "Making a Murderer," some questioned the manner by which it was conducted. On Aug. 12, a federal judge in Milwaukee overturned the conviction, ruling that investigators obtained Dassey's confession by offering "false promises" that he had "nothing to worry about." The document also noted Dassey's age and "intellectual deficits," and that the then-teenager did not "the benefit of an adult present to look out for his interests."

Lauren Nirider, Dassey’s attorney, released a statement to the Center on Wrongful Convictions of Youth’s website about the appeal.

"We are disappointed in the State's decision to prolong Brendan's case by seeking an appeal. We look forward to continuing to defend his rights in court. Like Brendan, we remain grateful to his many supporters for their continued loyalty and strength," she said.

Dassey will remain behind bars, pending the outcome of the appeal.