The woman is accused of conspiring to murder both her father and her former husband at the family cottage in Arboga, central Sweden.
Her former boyfriend has admitted to stabbing the father to death and seriously injuring her mother in August 2016.
After the stabbings, police began to investigate the drowning of the woman's husband near the same summer cottage the previous year, discovering the she had attempted to claim on a life insurance policy shortly afterwards.
“The murder and the attempted murder have brought with them the most consequences for those affected and there are several aggravating circumstances which should be take into consideration when setting the punishment,” Jessica Wenna, the prosecutor, argued at Västmanland District Court on Monday.
The Afghan man’s defence lawyer, Lars Jähresten, argued that his client should not be given a life sentence on the grounds that he had been under the age of 21 at the time of the stabbings. If true, this would limit the maximum possible sentence to 14 years.
"The most reliable information is what he has claimed for more than half a year – that he was born in 1996,” Jähresten said, pointing to an Iranian ID document.
”The prosecutor assigns the most importance to the fact that he has come forward with different ages previously. We have a document that shows that he was born in 1996.”
Amanda Hikes, the woman’s defence lawyer, also pushed for a lower sentence for her client, arguing that she had previously had a clean record, had not planned the attacks in advance, and had been under a lot of psychological pressure at the time of the killings.
The court found both guilty at the end of the trial in June, but decided to order psychiatric assessments before holding the final sentencing hearing.
Court psychiatrists ruled that the woman was not mentally disturbed on July 25.
The court said it would hand down its sentence on August 21.