A father has called for a change in the law after the hit-and-run driver who left his son with brain damage was jailed for 21 months.

Roy Phillips, whose son Graham will need round-the-clock care for the rest of his life, said: "The law is so out of kilter with the severity of the crime.

"I don't understand why Parliament doesn't do something.

"There's no parity between the crime and the punishment."

During the case at Leicester Crown Court, Judge Christopher Metcalf agreed, saying: "The sentence I pass is severely limited by the maximum penalty of two years for dangerous driving."

He added: "Myself and other judges have consistently drawn attention to the wholly inadequate sentencing powers for dangerous driving, on an offence that carries such a wide spectrum of seriousness."

He said the case was "at the top of the scale", but he had to give some discount for a guilty plea.

Rajesh Khunti (22) had been drinking at a party before driving a Honda Civic erratically, overtaking in the path of other vehicles, speeding and swerving.

He lost control and drove into Graham, a Leicester University student, who was crossing Evington Road, in the city, early on September 22, 2007.

Jeremy Janes, prosecuting, said Khunti left Graham (21) fighting for his life with severe brain damage.

Khunti, of Glen Street, Belgrave, later crashed and abandoned the Honda in Oadby.

Police found his mobile phone, house key and footprint on a seat inside the car. He tried to lie his way out of trouble the next day, insisting he had sold the car.

It was only on the day of trial, 16 months later, on January 19 that he admitted being the dangerous driver, having no insurance and failing to stop after an accident.

He had a previous conviction for dangerous driving in 2002.

After yesterday's hearing, Mr Phillips said the sentence was an insult to his son, who had been a sports-loving man on a mechanical engineering course.

He said: "In many respects it's a fate worse than death and this guy is going to be out in less than a year.

"If Graham hadn't survived, and he very nearly didn't, it would have been a maximum of 14 years for causing death by dangerous driving."

Graham, of Tennyson Street, Highfields, Leicester, was saved by the skill of neurosurgeons but is now bed-ridden and unable to speak.

Judge Metcalf told Khunti: "As a result of your driving, Graham Phillips is in an exceptionally damaged physical and psychological state."

Mary Prior, defending, said Khunti, who was also banned from driving for five years, was remorseful.

After months in hospital, Graham's American mum took him to be cared for in Austin, Texas.