This moves mobile phone theft up the sentencing tariff to place it alongside a sexual assault or grievous bodily harm

Harry Fletcher Napo

Napo's Harry Fletcher argued this could lead to pressure for a commensurate increase in sentences for these offences and subsequent overcrowding.

But he added there would be no influx of phone robbers to prison because of the low rate of successful prosecutions - just 5-7%.

The Lord Chief Justice, Lord Woolf, has said mobile phone robbers should expect a jail sentence of up to five years, and occasionally even more.

The tough sentences would apply "irrespective of the age of the offender and irrespective of whether the offender has previous convictions", he said.

Unknown accomplice

Dean Healey, from Brixton, south London, was jailed for four years at the Old Bailey on Wednesday after being told by the judge: "This type of offence will not be tolerated."

Healey and an unknown accomplice targeted their 17-year-old victim, Lee Staples, after he left an office party in Streatham in February last year.

Healey was sentenced to four years jail

The pair pushed him against a wall, punching and kicking him before snatching his wallet and phone, bought for �130 just weeks earlier.

Healey was arrested three days later and, with his victim's blood on his clothing, linked by DNA to the attack.

Both Mr Staples and his mother welcomed the tougher sentence.

But Mr Fletcher warned there could be knock-on effects in sentencing of other crimes and a better definition was needed.

"This sentence moves mobile phone theft, which is classified as a snatch theft, up the sentencing tariff to place it alongside a sexual assault or grievous bodily harm," he said.

Definition needed

"Are these more serious offences to get even higher sentences, which would play havoc on the prison population, already at a record high?

"Or will mobile phone theft have to be more carefully defined?

"Judges would have to make clear that these longer sentences are being applied to the serious cases where there is serious harm caused to the victim."

I am very pleased with the outcome - justice has been done

Lee Staples Victim

Passing sentence on Healey, who was convicted last month, Judge Valerie Pearlman told him she regarded the street robbery as so serious it warranted an immediate custodial sentence.

"The sentence I pass is to keep the public protected from you and as a deterrent."

It was "a bad case of gratuitous violence", she added.

Speaking outside court after the sentencing, Mr Staples told BBC News: "I am very pleased with the outcome. Justice has been done."

Mother's nightmare

He said after the attack it had taken some time to venture outdoors again. He looked over his shoulder in the street and was afraid to use his phone in public.

His mother, Lorraine Crawley, said: "This kind of attack is every mother's nightmare.

"When I saw Lee I didn't recognise him. His face was battered and there was blood everywhere."

The new sentencing regime has also been backed by the West Midlands Police Chief Constable Sir Edward Crew.

Sir Edward said he was "delighted" with Lord Woolf's comments and his decision to increase the sentences of two teenage muggers, one of whom was from Smethwick, West Midlands.

"Mobile phone robbers are a plague on our society and I have felt for some time that there needs to be a far more comprehensive strategy for dealing with them."