An investigator walks out of a fire-damaged home in Northwest Washington where four people were found dead May 20, 2015. The victims were Sav­­vas Savopoulos, 46, his wife, Amy, 47; their son, Philip, 10; and the family’s housekeeper, 57-year-old Veralicia “Vera” Figueroa. (Manuel Balce Ceneta/AP; Tony Powell/Washington Life Magazine)

The Maryland man convicted of killing three members of a Northwest Washington family and their housekeeper should spend the rest of his life in prison, prosecutors wrote in a court filing Monday.

Daron Wint, 37, who was convicted this past fall on 20 counts including first-degree murder, kidnapping and arson, is scheduled to be sentenced Friday in D.C. Superior Court in the slayings of Sav­­vas Savopoulos, 46, his wife, Amy, 47; their son, Philip, 10; and the family’s housekeeper, 57-year-old Veralicia “Vera” Figueroa.

“Death was not quick for these victims, nor was it painless,” Assistant U.S. Attorney Laura Bach wrote in her 17-page memo. “They were tortured — mentally and physically — for almost 24 hours.

“It needs to be made clear to Darron Wint what he did and the pain that he caused,” Bach wrote of Wint, who also goes by Darron. “He needs to hear the words repeated over and over again ‘life without the possibility of release.’ ”

During the six-week trial, prosecutors said Wint held the family hostage for a cash ransom. The prosecutors showed jurors graphic crime scene and autopsy photos to argue Wint viciously beat his victims with a baseball bat, stabbed them and then set their bodies and the Woodland Drive house on fire.

Prosecutors have long said they planned to ask Judge Juliet J. McKenna to sentence Wint to a prison term that would be the equivalent to life in prison if Wint were found guilty of the murders.

Philip Savopoulos in a family photograph presented during the murder trial of Daron Wint. (U. S. attorney’s office)

Federal prosecutors at trial portrayed Wint, a former employee at a Savopoulos family business, American Iron Works in Maryland, as a man driven by greed and vengeance.

Wint’s public defenders argued their client was innocent. They said that his brother and his half-brother were the killers and that Wint had been set up to take the blame. Wint was the only person charged.

Wint, who was born in Guyana in South America, moved to the United States with his family in 2000 and was living with his family in Lanham, Md., at the time of the killings.

Prosecutors alleged Wint broke into the Savopoulos home in May 2015 and held the victims hostage as he demanded $40,000 in ransom that Savvas Savopoulos had delivered to the home in the hope that the intruder would leave them unharmed.

Daron Wint (D.C. police/Reuters)

Prosecutors said Wint’s DNA was found on a discarded slice of Domino’s pizza that had been delivered to the house the night the victims were held inside. Authorities said they also found Wint’s DNA on a knife in the basement of the house and a hair matching Wint’s on a bed where the adults’ bodies were found. Several of Wint’s friends and family testified that they saw Wint with large sums of money, all $100 bills, in the days after the killings. They testified Wint told them he obtained the money from winning the lottery and selling his minivan.

In October, after just two days of deliberations, the jury of six men and six women found Wint guilty on all charges.

Wint and his public defenders have appealed the verdict, which could mean that Wint — who testified during the trial — will not speak at this sentencing.

Wint, Bach wrote, has “no empathy for the pain he inflicted and continues to inflict on these families each and every day. His violent and narcissistic history makes clear that Darron Wint has always cared about one person — himself.”