A POST-mortem examination failed to determine how Jenna Brookfield died, a jury was told yesterday.

Examinations of the 15-year-old proved inconclusive because she had been buried for more than two months before being found, Dr Derek James, consultant pathologist, told the jury at Cardiff crown court.

The Abersychan teenager's body was recovered from a "sea of mud" on November 18 last year, after she was found in a shallow grave around 15 to 18 inches in depth.

Her stepfather, Michael Baldwin, 36, formerly of Limekiln Road, Pontnewynydd, denies murdering his stepdaughter between September 3 and 11 last year.

The court has already heard that he told police he buried Jenna after she accidentally fell down the stairs while they argued.

Yesterday, Dr Derek James told the court that in cases where people have fallen down the stairs there is evidence of defence wounds, for example, on their elbows and knees. Dr James said he could not find any such wounds on Jenna.

David Aub-rey, QC, prosecuting, asked what injuries Dr James would expect to find on a person who had been strangled or suffocated.

The pathologist said tiny, pin-prick-sized red spots would appear around and behind the person's eyes, around the lining of the mouth and - in severe cases - anywhere on the head and neck.

The spots are caused by restriction of blood flow, a build-up of pressure and blood vessels bursting.

Mr Aubrey said: "Would you have expected to find these in the eyes and mouth because of decomposition?"

Dr James said: "No." He added the red spots would not necessarily have appeared if a person was strangled by somebody locking the person in the crook of their elbow or between the thumb and index finger.

It was also impossible for Dr James to carry out tests on Jenna's brain to determine whether or not she had suffered injuries causing it to swell or bleed.

During cross-examination, Peter Murphy, QC, said Jenna could have suffered defence injuries as a result of falling down the stairs.

But they could have been destroyed in the 12 weeks before she was found. Dr James said: "I cannot say she did not fall down the stairs."

When Jenna was recovered her clothes were caked in mud.

The prosecution told the court her trousers were undone and her top had "rucked up" to just below her chest.

Mr Murphy said: "Can you help as to when it was you first made a note of the clothing - after the body had been removed from the ground?"

Dr James replied: "No. It was difficult to work out at the time. Everything was so caked in mud."

Mr Murphy asked whether her top was "rucked up" before or after Jenna was lifted from the ground.

Dr James said: "She was actually in the ground with her clothing like that."

Mr Murphy asked when Dr James noticed Jenna's drawstring trousers, which also had a popper, were undone at the waist.

"I cannot remember when I made a note of that observation," Dr James said.

He added there was an attempt made to extract evidence from Jenna's fingernails, but some could not be taken.

Judge John Griffith Williams, QC, said: "Is it impossible to say whether there would have been any material relevant under the fingernails?"

Dr James said: "It's very difficult to detect two months down the line."

Mr Murphy moved on to two cuts found at the back of Jenna's head.

He said: "Certainly they are consistent with a fall down the stairs with the head striking something solid?"

Dr James replied: "Yes."