How long has the Government known about the prisons overcrowding crisis, and what has it done about it?

Prison overcrowding has dogged Labour since it came to power, with the earliest initiative to tackle the problem launched when Jack Straw was Home Secretary between 1997 and 2001. He introduced home detention curfew, which allowed low risk offenders to leave jail several weeks early as long as they were tagged and curfewed. The scheme was extended to allow offenders to be released on home detention curfew for the last four and a half months of their sentence.

Foreign national prisoners were also allowed to leave prison four and a half months early so long as they were deported immediately in another initiative intended to ease population pressures.

Prison governors have also been instructed to move low risk offenders serving under 12 months to open jails for the last 28 days of their sentence, and when this did not free up enough spaces the number of days was doubled to 56 days.

Other measures aimed at easing the crisis have included the former Lord Chancellor, Lord Irvine of Lairg, together with David Blunkett, the former Home Secretary, stressing that prison should be reserved for violent offenders with community punishment for low risk criminals.

Ministers have looked at using army camps and leasing ships to hold immigration detainees which would allow space in jails to be freed up for criminals.

A total of 19,000 prison spaces have been provided since Labour came to power including new jails and ready to use units which are erected in existing prisons.

When John Reid became Home Secretary he promised that a further 8,000 spaces would be provided by 2012. The first 350 will become available next month with the conversion of a disused psychiatric hospital at Maghull on Merseyside.

Why hasn't the Government been successful?

The Government's attempt to tackle the problem has failed because of a huge increase in criminal offences since Labour came to power and hard-line rhetoric on law and order which affects the atmosphere in which judges and magistrates operate.

Sentence lengths have become longer and arrangements for recalling offenders who breach licence terms have been tightened, meaning that more offenders are being returned to jail. And there has been a huge growth in the number of offenders given the new indeterminate sentence for public protection which effectively means they are in jail until the Parole Board judges they are no longer a risk to the public and can be released.

Also, a huge overhaul in sentencing, which was intended to rebalance the criminal justice system and stabilise the prison population, has not worked. It was based on the premise of reviving the use of the fine, but that has not happened. Instead there has been sentence inflation, in which offenders who would have been given a fine now receive a community punishment and offenders who would have receiving a community penalty get short jail sentences.

What type of prisoners will be released back into the community in the light of today's revelations?

An estimated 2,000 low-risk offenders serving up to four years are expected to be eligible for early release. They will be risk-assessed by prison staff, released on a licence and subjected to some form of supervision on release. If they break the licence arrangement, they will be liable for recall to jail.

What are the potential solutions to the overcrowding problem?

Since last October, police have provided 400 cells at police stations around England and Wales under Operation Safeguard, a long-standing arrangement with police under which in an emergency police cells are made available to the prison service to house offenders.

As the crisis deepened in recent days, the National Offender Management Service - the joint prisons and probation service - has held urgent talks with police in an attempt to secure a further 200 cells. But police have refused to provide that number, insisting they will help out as best they can on a daily basis. In addition, 141 cells at courts in six centres have been made available with more than 100 offenders held in recent nights. But, as the overcrowding has worsened, some prisoners have been held for two nights in cells at courts with mattresses put on benches, food bought in from outside and no showers.

Gordon Brown said today that further Treasury money would be given to solving this crisis. If the previous solutions haven't been successful, what options has he got?

Gordon Brown's promise could mean that more ready-to-use units could be purchased and placed in existing jails to ease population pressures which, together with the the early release, could give them a breathing space until new accommodation is built.

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