Jurors in the case of the man accused of killing relatives of Jennifer Hudson began deliberations late Wednesday afternoon after prosecutors insisted that "a tsunami of evidence" linked him to the crime.

The defence for the man accused of killing relatives of Jennifer Hudson told jurors that prosecutors failed to prove their case, while a prosecutor countered that they had "overwhelming circumstantial evidence" linking him to the crime.

Prosecutor Jennifer Bagby insisted during her closing argument that Hudson's former brother-in-law, William Balfour, is the killer and showed jurors photos of the victims' bloody bodies juxtaposed with pictures of them alive.

"This defendant is the one that made (them) into these images," Bagby said, glancing back at the photos.

Jennifer Hudson overcome

Hudson, who attended every day of testimony in her former brother-in-law's murder trial, bent forward, her head on her knee, and sobbed as Bagby described what she called "the execution" of Hudson's mother, brother and seven-year-old nephew in October 2008.

The boy's mother, Hudson's sister Julia Hudson, fiddled nervously with a piece of string as Bagby described how her ex-husband allegedly shot her son, Jason King, whom she called Juice Box, through the head.

'They know as they sit there that they have failed to prove the case'—Public defender Amy Thompson

Balfour "left that innocent child to die in his own pool of blood," covered by an old shower curtain, Bagby told jurors, who looked on intently, many of them taking notes.

Public defender Amy Thompson started her closing by pacing the room, walking up to Balfour and then toward the prosecution table, angrily pointing at the three state's attorneys.

"They know as they sit there that they have failed to prove the case," Thompson said almost at a shout.

"I am offended," she went on, "that they would ask you to throw your logic away."

Amy Thompson, defence attorney for William Balfour, said there is not enough evidence to convict her client. (M Spencer Green/Associated Press)

During her closing, Bagby laid the alleged murder weapon, a silver and black .45 handgun, on a podium feet in front of the jury, and it clanged as it hit the wood.

She said gunshot residue from it was found on the steering wheel of Balfour's green Chrysler. Bullets taken from the bodies were fired from the same gun, Bagby said.

"Make no mistake, there is physical evidence ... linking him to the murders," she said. And, she added, "You have overwhelming circumstantial evidence."

She took time to describe what circumstantial evidence is, saying it is everything short of a direct witness.

"Contrary to what you may have heard on television ... circumstantial evidence isn't lesser evidence," she said.

Last word to jurors

The last word to jurors was left to the lead prosecutor James McKay, who called the defence closing "desperate."

"Calling the defendant a dog is an insult to dogs!" McKay said, his voice soaring as he walked up to the defence table looking straight at Balfour.

McKay lashed out at Thompson, who had finished her closing minutes earlier.

"I don't know what the acoustics are like in this courtroom," McKay said after pointing at Thompson. "But what in the world was she listening to here (during two weeks of testimony)?" he shouted.

Prosecutors presented weeks of testimony, starting with Jennifer Hudson. She told jurors about the last time she saw her three family members alive and spoke endearingly about her nephew.

The defence called just two witnesses —two detectives who had testified earlier —in a bid to suggest investigators botched the triple-homicide investigation.

Balfour pleaded not guilty to three counts of first-degree murder. If convicted on all counts, he faces a mandatory life prison term.

Estranged but not divorced

Balfour and Julia Hudson were estranged but not yet divorced when the shootings occurred, and prosecution witnesses testified he threatened to kill the Hudson family dozens of times if Julia Hudson refused to reconcile with him.

Prosecutors say Balfour shot Hudson's mother, Darnell Donerson, 57, in the living room of the Hudson family home Oct. 24, 2008, then shot Hudson's 29-year-old brother, Jason Hudson, in the head as he lay in bed.

Balfour allegedly then abducted Jason and shot him as he lay behind a front seat of an SUV. His body was found in the abandoned vehicle miles away after a three-day search.