The Minnesota Supreme Court has declined to hear an appeal by Dakota County prosecutors, sending the case of Final Exit Network Inc. and the two remaining defendants accused of helping Doreen Dunn kill herself in her Apple Valley home in 2007 back to the trial court.

The state Court of Appeals ruled last fall in the Final Exit case that the state law that prohibits advising or encouraging suicide violates the right to free speech.

The county attorney’s office appealed to the high court, which put it on hold pending a ruling in another case. That was the case of William Melchert-Dinkel of Faribault, Minn., an ex-nurse who had been convicted in 2011 of “advising and encouraging” the suicides of a man in England and a teenager in Canada.

The Supreme Court reversed Melchert-Dinkel’s convictions in March, ruling that the “advising and encouraging” language in the law is unconstitutional. The justices’ ruling still allows prosecution of people who directly assist in a suicide, which could include a physical act or even the use of speech.

Final Exit Network and Lawrence Egbert still face charges of assisting a suicide; aiding and abetting assisted suicide; interference with a dead body, and aiding and abetting interference with a dead body. Roberta Massey is charged with aiding and abetting assisted suicide.

Similar charges against a third defendant, Thomas Goodwin, the group’s leader, were dismissed by Dakota County District Judge Karen Asphaug in March 2013. A fourth defendant, Jerry Dincin, has died.

The county attorney’s office charged Final Exit and the four in May 2012, about five years after Dunn, 57, used helium and a plastic bag to end her life.

Dunn had made an “exit request” in January 2007, writing that she was “living with unbearable, excruciating chronic pain that has spread throughout my whole body since 12/96.”

Two Final Exit members were with her the day of her death, but Robert Rivas, an attorney for Final Exit, said in 2012 that he didn’t know if they were with her when she died.

Phil Prokopowicz, chief deputy county attorney, said his office has put in a request with Judge Asphaug to set up scheduling for the trial and any additional hearings that are necessary. It is possible that the trial could begin later this year, he said.

“We can’t argue that [they] encouraged suicide,” Prokopowicz said. “So we lose potential theories, but we can move forward with the case.”

Rivas said Wednesday that it’s not surprising that the Supreme Court denied the prosecutors’ appeal and his cross-appeal since the Court of Appeals ruling in the Final Exit case “almost exactly” matched the high court’s ruling in the Melchert-Dinkel case.

The significance of the case returning to the lower court “is that it affects all of the evidence,” Rivas said. “The trial court is going to have to try to exclude evidence that the defendants did anything to advise or encourage. The trial court has to guard against the state trying to make its case with those activities.”

Rivas added that prosecutors “confirmed to me that they are not going to attempt to seek review in the U.S. Supreme Court.”

The state Supreme Court’s denial was filed June 17.