Four teenagers have each been jailed for up to 15 years for the killing of a man with the mental age of a nine-year-old.
The young men from Greenford and Acton were jailed today, Thursday, October 2, at the Old Bailey.
Jamal Jones, 17 of Newport Road , Acton, was sentenced to 15 years for murder.
Michael Mensah, 18 of Brants Walk, Greenford, was sentenced to 15 years for manslaughter and nine years for attempted robbery, to run concurrently. He also received two years for robbery after being found guilty of robbing a 15-year-old boy in a separate incident.
Miguel Leiba, 17 of Framfield Road, Greenford, was sentenced to 14 years for manslaughter and eight years for attempted robbery to run concurrently.
Ryan Beresford, 19 of Winchester Street, Acton, was sentenced to 15 years for manslaughter and nine years for attempted robbery to run concurrently.
All four were convicted at the Old Bailey for their involvement in the death of Dean Mayley, who was 24 but had a mental age of nine due to a brain disorder.
They were found guilty on Thursday, August 28 following a hearing at the Old Bailey.
Investigating officer Detective Inspector Mark Lawson, from the Homicide and Major Crime Command, said: "The defendants were a team of robbers who, armed with a knife, were scouring the area that day looking for someone to rob.
"They had not a moment's hesitation in using that knife when Dean didn't immediately hand over his property. The knife was plunged into his heart; there could be no doubt of the defendants' intentions.
"Dean's family remain horrified and devastated by his needless death at the hands of these cowards and I hope their conviction today goes some way to helping them begin to move forward with their lives."
In a statement from Dean's mother Donna Mayley , she said: "My Dean had only just started travelling alone. He used to travel around with his dad up until his dad passed away in June 2013. Dean would make the simple trip from our home to his uncle's house in Greenford. He was murdered for nothing at all.
"It won't bring our Dean back but at least no other family will have to go through what our family has been through.
"Our family will never be the same again, the youngest of our family has had his life cut short for no reason and we will all struggle to come to terms with this for the rest of our lives."
On the afternoon of Friday, February 7, Dean, who lived in Northolt, was walking home along Ruislip Road, Greenford, when the four defendants spotted him. They were out in Mensah's Fiat Punto looking for likely victims to rob at knifepoint.
It is thought Dean, who suffered from microcephaly, caught their eye due to his distinctive North Face jacket and because he was alone.
They pulled over and Jones, Leiba and Beresford got out, Jones armed with a knife.
Jones approached Dean while the others went past him, blocking any chance of him escaping.
It's thought that Dean's condition meant he didn't readily understand what was happening and he didn't hand over any of his property during the confrontation.
Jones then stabbed him, straight into his heart, before all three ran off back to the car.
Dean staggered into the street and collapsed. Passers-by went to help him and police and the London Ambulance Service attended at 5.50pm. Despite their best efforts he died less than two hours later at St Mary's Hospital at 7pm.
The court heard that two youths had carried out another robbery a week earlier, at 8.50pm on Tuesday, 28 January 2014, on the same road, picking on a 15-year-old boy who was also wearing a North Face jacket. Again armed with a knife, they forced him to hand over his phone and coat.
The victim did not know who the suspects were - but the getaway car used in the robbery was traced to Mensah.
Mensah and Jones were arrested on Saturday, February 15 at their home addresses and Beresford and Leiba on Monday February 17 after detectives released CCTV images of them. Having seen the publicity, they handed themselves into Colindale police station.
