A pathologist told the murder trial jury of a Keighley man accused of killing his stepson 23 years ago the toddlers’ injuries did not fit the explanation given at the time.

Stephen Knox 53, now of Ingrow Lane, is accused of pushing two-year-old Mark Harrison down a flight of stairs at their home in Leicester in December, 1986.

A coroner recorded a verdict of accidental death after Knox told police the youngster slipped and accidentally fell down the steps, causing internal brain injuries, Nottingham Crown Court has heard.

But pathologist Dr Clive Bouch said Knox’s account did not explain an injury he found on the back of Mark’s head during a post-mortem examination following his death.

“Sufficient force had been applied to cause the fatal injury,” he said.

“That was not satisfactorily exp-lained by the information I was given at the time of the post-mortem, which I raised at the time.

“Because no other information became available I had to consider the possibility this child may have fallen at another time, other than falling downstairs, which wasn’t witnessed by anyone.”

Dr Bouch added that when he examined Mark’s body, he noted several bruises on his face, aged “at least a few hours, and at most two or three days” old.

He also discovered bleeding inside the skull and swelling of the brain.

However, under cross-examination from Mark Wall QC, Dr Bouch admitted that although he would almost certainly have carried out a detailed examination of Mark’s brain, he could find no notes from the procedure.

Mr Wall said that, if there had been no brain examination, something else may have caused the toddler’s death, such as a brain tumour or water on the brain, which may have been missed.

Dr Bouch said there would have been “no reason” to depart from his usual procedure of examining the brain. He said: “I see no reason why I would not have done it, when I did in every other case. I just can’t explain it.”

Knox was arrested in 2007 after Mark’s sister, Kerry Harrison, told a counsellor that she had witnessed him push her brother down the stairs as a three-and-a-half year old because he was being noisy.

Miss Harrison, now 26, said Knox had threatened her with the same fate if she told anyone what had happened.

The young siblings were living with Knox with their mother, Margaret, in Leicester after she left her husband.

Knox denies murder and the trial was expected to continue today.