CHICAGO (AP) — An American woman accused of helping to kill her mother and stuffing her body in a suitcase during a luxury vacation to Bali nine years ago changed her plea to guilty in Chicago federal court on Friday. Her lawyer said later she hoped to avoid a sentence of life behind bars by doing so.

Heather Mack pleaded guilty to one count of conspiring to kill Sheila von Wiese-Mack with her then-boyfriend to get access to a $1.5 million trust fund. Mack, then 18 and pregnant, covered her mom's mouth in a hotel room while Tommy Schaefer bludgeoned her with a fruit bowl, prosecutors say.

The change-of-plea hearing is the latest chapter in a story that has garnered international attention in part because of photographs of the suitcase, which seemed too small to hold an adult woman’s body.

Mack, now 27, appeared calm and confident as she stood in orange jail garb and orange slippers, occasionally brushing her hair from her eyes as she answered the judge's questions — saying she knew she was giving up her right to remain silent at the hearing.

After Mack paused before saying she understood the plea agreement hammered out with prosecutors in preceding weeks, U.S. District Judge Matthew Kennelly noted the hesitation and asked again if she was sure she fully understood it.

“Yes, your honor,” she responded.

Two other charges against Mack would be dropped at the end of the sentencing process. Schaefer was convicted of murder and remains in Indonesia, where he is serving an 18-year sentence. He is charged in the same U.S. indictment.

After the hearing, relatives of Wiese-Mack issued a statement saying they were “very relieved that the mastermind of Sheila’s murder admitted her guilt today.”

“We will continue to be our sister Sheila’s voice throughout the sentencing process to ensure that real justice is served,” they said.

The plea agreement calls for a sentence of no more than 28 years, though Kennelly told Mack he hasn't yet decided whether to accept that sentencing cap. If he rejects it, Mack could withdraw her plea, and either hold fresh plea discussions or go to trial. The judge set a Dec. 18 sentencing date.

A key issue that wasn't decided in talks between prosecutors and the defense prior to Friday's hearing was whether the years Mack spent in prison in Indonesia for a 2015 conviction of being an accessory to Wiese-Mack’s murder would be subtracted from whatever U.S. sentence is imposed by Kennelly.

Mack, who lived with her mother in suburban Chicago’s Oak Park, served seven years of her 10-year Indonesian sentence. She was deported in 2021 and U.S. agents arrested her immediately after her plane landed at Chicago’s O’Hare International Airport.

Mack's lawyer, Michael Leonard, told reporters after the hearing that his client's decision to plead guilty was motivated in part by wanting to avoid a sentence of life in prison — something that would be off the table under the plea deal, if the judge formally OKs it.

In arguing for leniency at sentencing, Leonard said he would present evidence that Mack has matured and that she was “a fantastic mother" to her and Schaefer's daughter, who she gave birth to in Indonesia after her arrest.

“She is certainly not the person she was,” Leonard said. “She has grown as a human.”

Her then-six-year-old daughter was with her when Mack was arrested at the Chicago airport. The girl was later placed with a relative after a custody fight.

Leonard said Mack was able to spend time with her daughter while serving her sentence in Indonesia and that her child was now her top priority.

“The most important thing for her is reunification with her daughter,” he said.

In successfully arguing against bond for Mack in 2021, prosecutors said she and Schaefer had planned the killing for months. They also said they had video evidence that showed both Mack and Schaefer trying to get the suitcase with Wiese-Mack’s body inside it into an Indonesian taxicab.

Some relatives of Wiese-Mack had complained that the Indonesian sentence was far too lenient. In filings, prosecutors said the U.S. charges don’t violate constitutional prohibitions against prosecuting someone twice for the same acts, including because the U.S. charges allege conspiracy and other acts not included in the Indonesian case.

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