The justice system was in turmoil last night after a judge allowed a killer driver to walk free because Britain's prisons are full.

Ambulance driver Malcolm Legrys became the latest to escape jail despite committing a serious offence.

The Home Office is now facing a crisis and the Home Secretary under the threat of a growing rebellion by judges furious at being told to jail only the most dangerous offenders.

Judge Charles Kemp had told Legrys, 59, from Hassocks, when he was convicted last month to expect a jail term.

But yesterday Judge Kemp pointedly told Lewes Crown Court he was setting Legrys free because the jails are full.

He said he had to consider "the current situation in the country's prisons".

He told Legrys: "The courts are repeatedly reminded that scarce prison places should be filled with violent or dangerous offenders from whom the public need to be protected. In my view you are not such a person."

Legrys killed motorcyclist Matthew Bailey, 31, from Crawley Down, in a head-on crash on a country road in Ardingly, near Haywards Heath, in January last year.

Family and friends of Mr Bailey reacted with anger and tears as Legrys walked free from court.

His father walked out of the court as the sentence was passed and his mother said tearfully: "It is not fair. Is that all he is worth?"

A friend among those packing the public gallery described it as "a joke".

A spokesman for the Crown Prosecution Service said it was considering appealing against the sentence.

He said: "The CPS will consider all the relevant material before the judge and decide whether the case should be referred to the Attorney-General for a potential referral to the Court of Appeal as an unduly lenient sentence."

The sentence heaps further pressure on Home Secretary John Reid as a growing number of serious criminals walk free from court.

The fiasco has infuriated Labour MPs who fear the party's record on law and order is being destroyed.

Des Turner, who represents Brighton Kemptown, said: "I think it's stupid we're letting quite so many people out - it neither protects the public nor helps criminals to reform.

It's getting a bit messy, I have to say.

"We haven't got it right - the punishment should befit the crime and should protect the public. At the moment we are not doing any of those things terribly successfully.

"But we don't want to get like America where the prison population is outrageous. It's depressing to have to keep building new prisons."

Mr Reid's order that only the worst criminals should be sent down because there is no room in prison was made in January.

Its full impact became clear yesterday when Legrys was given a 12-month sentence,suspended for two years, ordered to carry out 200 hours of unpaid work and banned from driving for just two years.

For the offence of causing death by dangerous driving, the Sentencing Advisory Panel advises that, to mark the gravity of an offence resulting in death, the starting point for sentence should normally be imprisonment.

It recommends a short custodial sentence for an offence arising from a momentary error of judgment and a custodial sentence of up to five years when the standard of the offender's driving is more dangerous.

Legrys, a father-of-three, had been trying to overtake a tractor and trailer which had no lights, as well as a pick-up truck, when he ploughed into Mr Bailey.

He denied causing death by dangerous driving but was unanimously convicted after a week long jury trial last month.

Judge Kemp told Legrys, who resigned from his job with the ambulance service after the fatal accident, the offence was serious enough to warrant a jail sentence but he was taking into account the dangerous driving on that day was a momentary error of judgement by someone who was normally a cautious driver.

The judge said he was also taking into consideration Legrys's good character and believed the tractor's lack of lights had substantially contributed to the accident.

But, passing sentence, Judge Kemp told Mr Bailey's family: "I appreciate the sentence I have passed may not appear to meet your requirements."

The Legrys case is the latest in a series of apparently lenient sentences handed down by judges amid the burgeoning prisons crisis.

Paedophile Keith Morris, facing a 14-year sentence for serious sex offences against a teenager, was released on bail in January, despite concerns that he had been hanging around a school.

Morris had a string of previous convictions and had been jailed in the past, admitting to police he has "a problem with children".

Days later, Judge John Rogers suspended a six-month sentence on Derek Williams for downloading child pornography because of the Home Office's request to consider guidelines which offer an alternative to custody in all bar the worst cases.

Williams himself admitted he had been "lucky".

Criminals were also quick to realise that now was a good time to try their luck.

Serial shoplifter Kevin Morrow told police who arrested him that he would be let off because "the prisons are full" and sure enough escaped with a £50 fine from magistrates.

Despite criminals who would normally have been locked up going free, the prison population remains at 80,000.

Earlier this year, the Lord Chancellor admitted more cases would follow of criminals being freed because the jails were full.

Nick Herbert, shadow minister for policing and MP for Arundel and South Downs, said: "It must be wrong to have a situation where a judge feels unable to give a custodial sentence simply because there isn't sufficient prison capacity."