Aaron Schnagl was portrayed Monday as a remorseless drug dealer who dumped Danielle Jelinek's body in a Chisago County pond after she died of a cocaine overdose in his bedroom.

"The life of Danielle Jelinek was just the cost of doing business," prosecutor Ryan Flynn said of Schnagl, now 31, who's charged with third-degree murder.

Schnagl carried Jelinek's body to the pond, in a blizzard, and pushed her into the icy water, Flynn said. "The defendant … later stated to another [person], 'She will never be found,' " Flynn told the jury during his opening remarks in a trial that could last at least two weeks.

But defense attorney Melvin Welch, noting Jelinek's struggles with drug addiction, said Schnagl awoke that morning in December 2012 to find her gone from his house in Chisago Lake Township after a night of alcohol and cocaine.

"At some point in the middle of the night, Miss Jelinek went missing," Welch said.

Five months after Jelinek's family alerted authorities, the search ended in May 2013 when her body was found in a pond about a quarter-mile from Schnagl's house.

Schnagl was indicted on the murder charge in December 2013, accused of causing Jelinek's death by providing her with illegal drugs that killed her unintentionally. An autopsy showed cocaine and alcohol in her body.

Jelinek, 27, of Oakdale, was a manager at the Wells Fargo branch bank in Maplewood. The afternoon before she disappeared, she had told her sister, Cory, that she was going to see a girlfriend. Instead, she went to meet Schnagl. They went shopping and then to buy cocaine, Flynn said.

It was clear from the outset of Monday's testimony that prosecutors wouldn't try to hide from jurors Danielle Jelinek's drug addiction, which began in high school, or the fact that her apparently nonromantic relationship with Schnagl included sex.

Cory Jelinek, the first witness called by the prosecution, described her sister as someone who "just had this beauty and spirit about her. It captured everyone."

But she also said that Danielle was a different person when she began using methamphetamine as a teenager, and at times seemed indifferent toward her close family.

Danielle went through drug treatment three times and recovered in a halfway house, Cory said. After that, she testified, the sisters lived together at Cory's residence in Oakdale for more than two years, a time during which Danielle was off drugs.

Questioned by Chisago County prosecutor Nick Hydukovich, Cory Jelinek said her sister met Schnagl in July 2010. After Danielle disappeared, Cory called Schnagl and exchanged several text messages with him as she became increasingly worried about her sister's whereabouts.

Schnagl told Cory Jelinek that he saw tracks in the snow outside his house, suggesting Danielle had walked off. When she asked for his home address, he gave the location of an automotive shop miles away.

Welch, in a short cross-examination, asked Cory Jelinek which members of her family began looking for Danielle. She said it was her father and Danielle's former boyfriend, and that they had gone to Chisago County in search of her.

Welch objected repeatedly to what he said was the prosecution's attempts to mention evidence that already had been ruled out, and to what he said were argumentative comments. He also asked District Judge Todd Schoffelman to declare a mistrial. Schoffelman overruled the motion for mistrial and most of Welch's other objections.

Much of Flynn's opening remarks included references to drugs found at Schnagl's house after a law enforcement investigation began. When Schnagl later gave a written statement at the sheriff's office, he described Danielle Jelinek as a drunk and "cokehead," Flynn said.

Chisago County sheriff's deputies initially removed 12 pounds of marijuana contained in two boxes from a vehicle in Schnagl's garage, according to court documents. Unidentified pills also were removed, and 29.2 grams of cocaine was discovered.

Schnagl previously was sentenced to 78 months in prison after he pleaded guilty to a charge of second-degree cocaine possession. The sentence runs concurrently with an 86-month jail term Schnagl received after another drug conviction in Anoka County.

Schnagl is serving time in Rush City prison but being held in the Chisago County jail for the trial, which continues Tuesday at the county courthouse in Center City, Minn.