Deputy Chief Constable Bill Brereton saw his daughter fall

Deputy Chief Constable Bill Brereton made the claims during an inquest into the 20-year-old's death on Wednesday.

Jenny Brereton was thrown from her Suzuki bike on the M53 in Wirral in May 2001 when a tailpack piece of luggage came loose.

The Crown Prosecution Service brought no charges against Oxford Products Limited who manufactured the equipment.

Wirral Coroner's Court was told the product caused the back wheel to lock, throwing her from the machine.

Daughter killed

Miss Brereton died in hospital from brain damage six days later. A verdict of accidental death was recorded.

Oxford Products had previously put out a product recall warning regarding the tailpacks.

They also paid �2,500 compensation to a motorcyclist who crashed in similar circumstances to Miss Brereton in July 2000.

During the inquest Mr Brereton told coroner Christopher Johnson that the firm "killed my daughter".

"Oxford Products know their products are dangerous," he said.

"This was an unlawful killing."

The family have said they will discuss any further action against the company with their legal advisors.

Jenny Brereton had been studying mechanics at Wirral Metropolitan College with a view to working with motorbikes once qualified.

I started to flash Jenny, I'm not sure if I actually did. I think I did but things happened very fast Deputy Chief Constable Bill Brereton

The court heard that she bought the Oxford Products luggage by mail order the month before the accident.

The bag should have had four plastic straps but Mr Brereton said they never arrived.

He was riding behind his daughter as they travelled to Donnigton Park near Leicester and witnessed the horrific accident.

Choking back tears, Mr Brereton told the inquest he saw the tailpack come loose and tried to warn his daughter.

"I clearly remember the blue tailpack starting to look loose. It didn't look right.

"I started to flash Jenny, I'm not sure if I actually did. I think I did but things happened very fast.

"The next thing the bag came loose and fouled Jenny's wheel," he said.

He told the coroner he saw his daughter's body thrown from the bike and "shaken like a rag doll" against the carriageway.