A teenager from Nottingham has been found guilty of murdering a man at a crowded city-centre bus stop.
Rickell Patterson said he was trying to defend himself
Rickell Corey Patterson, 17, from St Ann's, was cycling on the pavement when his victim Timothy Smith, 40, accidentally walked into his bike.
Patterson, who had admitted manslaughter but denied murder, will be sentenced on Friday.
The court heard Mr Smith, a former Rutland Times reporter, was on his way home from the library at the time.
Patterson stabbed Mr Smith through the chest, but argued it was in self-defence.
He said he was frightened because one of his friends from St Ann's had been threatened by a group from another part of the city - and was trying to defend himself by stabbing Mr Smith's arm.
Patterson handed himself in to the police the following afternoon after his mother found out what had happened.
He told the police where to find the bloodstained knife, which was later shown to the jury.
Mr Smith's family said their lives had been shattered by his murder.
His mother June, 77, said she was heartbroken.
"Does the person who did this have any idea at all of what he has done? Tim's brother Chris and I are now serving a life sentence of misery and grief," said Mrs Smith.
Tim Smith was on his way home when he was stabbed
"Why was he taken from us for absolutely no reason? It was so trivial.
"Tim was a beautiful person, kind, gentle, honest and always smiling.
"How can a 16-year-old take my son's life for no reason at all? I can't live with it."
Chris Smith, 42, described the effect his brother's death had had on him.
"I had to go and identify my brother in a morgue. I've held his birth certificate and his death certificate in my hand and stared at them.
"Do you know what that's like? It takes everything you have and strips it from you; it's left me an empty shell, overwhelmingly lost.
"The world is a poorer, poorer place now."