The driver of a tractor who drank the estimated equivalent of 13 pints of beer the night before he ran over and killed an 11-year-old boy on a farm has been jailed for a year.

Gary Green, 51, was more than two times the legal drink drive limit when the incident happened near Leeds in August 2013.

Green was originally arrested on suspicion of causing death by dangerous driving and drink driving, but an inquest into Harry Whitlam's death last year heard the case went no further because the incident happened on private land.

Most traffic offences only apply to public roads.

Green claimed he had drunk four pints in a pub the night before the incident, followed by two cans at home, but Judge Guy Kearl QC heard that an expert had concluded that he must have consumed the equivalent of 13 pints of beer before going to bed at 2am.

On Tuesday Green was jailed for 16 months and two weeks at Leeds Crown Court for health and safety violations which contributed to the death of the schoolboy at Swithens Farm.

Harry's mother Pamela, who worked in the farm's cafe and had taken him to the farm on the day he died, is calling for a change in the law.

Ms Whitlam, said: "It is not OK for anyone, whether on a public road or private land, to be drunk and get behind the wheel of a vehicle.

"My hope today, now the court process is complete, is that Harry's life becomes more than one day and as a family we can again remember the good times we shared.

"The day we lost Harry our close-knit family was changed forever.

"We all miss him dearly and it has not got easier with time but harder.

"Harry was my youngest son, a much-loved brother, grandson, nephew and cousin.

"The only memories I currently have of Harry are from the day of the accident but his life was so much more."