A 23-year-old burglar has admitted sexually assaulting and murdering a vulnerable 89-year-old woman in her own bed, changing his pleas part-way through the trial.
Widow Dorothy Woolmer was attacked in Tottenham, north London, in August last year, while Dempster was on the hunt for money to feed his drug habit.
He admitted one count of murder and two of sexual assault by penetration.
Prosecutors at the Old Bailey decided against proceeding with a further count of rape.
The court heard Ms Woolmer, described by her family as "feisty" and "independent" but who was just 4ft 11in tall and had osteoporosis, suffered severe injuries to her head and groin area after being attacked by Dempster at her home in Waltheof Gardens in August last year.
Court heard how Mrs Dempster was battered about the head numerous times
Pictured above is a court sketch of 23-year old Reece Dempster
He spent around seven hours in Ms Woolmer's home after breaking-in through a back door, arming himself with a truncheon he found in a downstairs cupboard while looking for cash.
Mrs Woolmer's lifeless and bloodied body was found semi-naked, in her bed by her sister and a close friend who were concerned when the pensioner failed to answer the door for her morning newspaper.
Prosecutor Anthony Orchard QC told jurors how Dempster had carried out some gardening work for the victim the previous month and returned to burgle her, breaking in just before 11pm finding Mrs Woolmer asleep in bed.
"He attacked her, battering her about the head numerous times, probably because he wanted to know where the money was kept, before sexually assaulting her," Mr Orchard said.
Dempster, who is 6ft 3ins, fled the scene the following morning, just before 6am, and went to his father's house nearby, vomiting several times on the way.
He left the property with his father nine minutes later, wearing a change of clothes, the court heard.
Dempster allegedly told his former partner Nikita Richards: "Nik, I need to tell you something.
"The other night I was around my dad's house with my Dad and (Dempster's brother) Aaron.
"We were smoking crack and drinking 3 or 4 bottles of gin and I was completely f***ed.
"I went off and I went to rob a house. I think I hurt someone."
The court heard Ms Richards asked what he meant and Dempster replied: "You have to understand I was smoking crack and drinking gin, I just blacked out and then I turned a light on and there was blood everywhere.
"And then I ran."
He added: "It's really bad, it's really bad. I wasn't expecting anyone to be in there. I'm going to be in so much trouble."
Dempster will be sentenced on Thursday.
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