Bradleigh Shepherd aged 25 of John Street, Heywood, was sentenced to three years and two months imprisonment, four years after an attack on Stephen Rimmer.
He had earlier pleaded guilty to manslaughter.
The attack happened on Culvert Street close to his home in Rochdale in August 2019, where Stephen was punched in the jaw by his stepson. He received serious facial injuries as a result.
One week after the assault, Stephen, who was 42 at the time, attended Accident and Emergency at the Royal Oldham Hospital for treatment for a fracture after suffering bleeding the night before. He unfortunately suffered a heart attack whilst with medical professionals.
Sadly, he did not fully regain consciousness and despite their best efforts he passed away in March 2020.
Medical evidence showed a link to the punch suffered to the jaw contributed to his death.
Subsequently, Greater Manchester Police launched a murder investigation. Officers uncovered incriminating text messages and a conversation where Bradleigh Shepherd admitted his surprise that the one-punch attack would break his jaw and cause the injuries it did.
In a tribute issued at the time of Stephen’s death, his family said; “Stephen was a caring son and brother, and a wonderful stepfather to Kimberley. He was also very popular with friends.
“Stephen was loving and kind; he touched the hearts of many. He was a gentle giant who lived his life to the full.
“His death has left us utterly devastated. We would like to take this opportunity to thank everyone during this awful time for their support.”
On the sentencing, Detective Chief Inspector Nicola McCulloch of GMP’s Major Incident Team said: “This is a very upsetting case that has cost the life of Stephen. The investigation contained complex medical evidence and took a number of years to complete, demonstrating how we will not give up and continue to investigate until we find the truth.
“I wish to thank Steven’s family for their patience and we hope that the conviction and sentence will give them some form of comfort and ease their pain slightly after losing a loved one in this devastating way.
“Unfortunately, we have seen over the years how one-punch assaults can have devastating consequences and again on this occasion, it goes to show how actions, whilst in rage, can have fatal repercussions.
“We would encourage anyone who believes they are a victim of any form of domestic violence to contact GMP at the earliest opportunity so we can provide the support you need.”
