Far too many people are being imprisoned in England and Wales, the country's top judge has warned.
Lord Phillips believes two-week jail terms are pointless
Lord Chief Justice Lord Phillips told the Guardian that offenders should be rehabilitated in the community, and be sent to jail only as a last resort.
He told the newspaper that short prison sentences were pointless.
Lord Woolf, another senior judge, told the BBC more people were being put in prison because judges no longer had enough discretion over sentences.
The judges' comments come as the prison population of England and Wales stands at 77,640 - about 2,000 short of capacity.
Lord Phillips, who succeeded Lord Woolf as lord chief justice, warned that overcrowding in prisons was "absolutely fatal" for treatment of prisoners.
He told the Guardian that judges should only jail offenders if there was no other option, but said there was no point in imprisoning someone for two weeks.
He also claimed drug addicts were deliberately committing offences to get on to prison help programmes.
"We need much better drug rehabilitation facilities in the community," he told the paper.
The Home Office said its drugs policy was delivering tangible benefits, a spokeswoman saying "record numbers of drug misusers are entering treatment".
Meanwhile, Lord Woolf told Radio 4's Law in Action programme it was important to avoid "talking up" sentencing.
He reserved particular criticism for the Sentencing Guidelines Council, which was set up by the government to promote consistency in sentencing.
But the former lord chief justice said the council's guidance helped to increase the severity of sentences.
"It puts [sentences] up because it reduces the discretion of the individual judge."
He described politicians "knocking" individual judges as an "open goal" because judges cannot respond, but said it was an "own goal".
"If you knock and knock and knock again at individual judges, in intemperate terms, then really it is very damaging," he said.
Lord Woolf defended the Human Rights Act and said that tension between the government and judiciary is a good thing.
In England and Wales 143 people out of every 100,000 are in jail - the highest rate in Western Europe.