Although the jury took under four hours to find Johnson guilty of dragging Miss O’Donnell from her bike, raping her and then strangling her to death with her own bra, the defendant defiantly maintained his innocence throughout.
As the sentence was passed he addressed Judge Glenn Bronson, saying: ‘I understand how the family feel about their loss, but how can you clearly say I did anything?
‘I didn’t do nothing. I understand where they coming from, but I didn’t have nobody die the way they said. I didn’t have no interaction with her.’
Judge Bronson replied that he had ‘not one scintilla of doubt’ that Johnson had committed the crimes, saying he had never felt more certain of a defendant’s guilt in 31 years as a lawyer and a judge.
He told Johnson his refusal to accept responsibility was ‘in keeping with your history of a lack of remorse.’
According to The Philadelphia Inquirer, the defendant shook his head and looked down at the table as the verdict was read, while his family burst into tears and one of his siblings fled the courtroom.
Around 30 of Miss O’Donnell’s relatives and friends were present, and her family gave victim impact statements to the court before the sentencing.
The victim’s tearful mother Rachel O’Donnell urged the judge to award the longest possible prison term.
She said of her daughter: ‘She was as good as a person could possibly be. Every minute that he sits there breathing oxygen is a chance she’ll never get…I don’t want anybody to ever have to run into him again.’
Miss O’Donnell’s aunt Heidi O’Donnell added: ‘He [Johnson] has no idea what he did to all of us. He should never ever be able to walk on the same ground that Sabina did. He should never be able to look at trees and walk on the beach.’
CBS Philly reported that Johnson had previously admitted the attack on Miss Johnson, saying he had only meant to steal her bicycle. He allegedly said he killed her because she screamed when he tried to take the bike.
He later retracted the confession, which his lawyers claim he made only because he is mentally challenged.
The prosecution in the case relied on DNA evidence and video surveillance to prove that Johnson dragged his victim to within yards of her apartment building before raping and strangling her.
Philadelphia District Attorney Seth Williams said in a statement: ‘My heart continues to go out to Sabina’s family and friends. I hope this verdict will give them some sense of justice.’
Standing outside the courtroom for the final time, Miss O’Donnell’s stepfather Mark Rounds tearfully hugged his wife and the jurors.
‘I’m just glad the police did their job as well as they did it and the Assistant District Attorneys did their jobs as well and as thoroughly as they did,’ he said.
According to the Philly Metro, Mr Rounds said he is not a supporter of the death penalty, and that he was satisfied with the sentence.
‘I hope the rest of society is satisfied as well,’ he said.
While they have now received the verdict they had yearned for, the O’Donnell family have waited almost two years to watch their daughter’s killer get life.
A dog walker found the young woman’s body, which was naked apart from a pair of beige socks, on 2 June 2010.
During the first two days of Johnson’s trial, the jury heard how he grabbed his 5’3, 100lb victim when she was riding her pink and grey bike home from a night out.
He grabbed her at the front of her apartment building, before dragging her 120ft to the rear of her home, where he raped and then killed her.
Assistant District Attorney Richard Sax told the court that O’Donnell was: ‘Tiny, small, petite but so vulnerable. Perfect prey.’
He said Johnson’s stalking of her on a bicycle, which was captured on CCTV to be played later on in the trial, happened because: ‘He knew he could dominate, overwhelm and control her.’
He claimed Johnson left his DNA ‘all over her, inside of her’ and said ‘he destroyed her’ during the attack.
Defence attorney Lee Mandell rejected the claims, arguing that even DNA experts were capable of making mistakes.
A forensic psychologist, Gerald Cooke, then testified that Johnson had an IQ of just 73, and had most likely been born with brain damage.
He said he acted like an 11 or 12-year-old and had smoked marijuana and drunk alcohol for many years.
Dog walker Christina Sirochman said the victim was clad only in her socks when she found her dumped body on June 2, 2010.
Ms Sirochman told a jury the victim had a swarm of flies around her mouth, but that she touched her to see if she was alive.
‘It was just like touching a piece of glass,’ she said. ‘That was somebody’s child and I didn’t want her to be alone.’
Other witnesses said they found a man’s dirty t-shirt and Miss O’Donnell’s purse in the hours after the murder.
Assistant Medical Examiner Edwin Lieberman, who performed the autopsy, said the ligature which ended Miss O’Donnell’s life was ‘one of the tightest’ he had seen.
He added that it would have taken 30 seconds for the victim to fall unconscious, and another three to five minutes of ‘continuous pressure to the neck’ to kill her.