The government should consider very seriously "sensible amendments" to its bill on paramilitary fugitives, a former Labour NI Secretary has said.
There are 150 people on the run from terror charges
The proposals cover up to 150 people wanted for crimes committed before the Good Friday Agreement in 1998.
Paul Murphy acknowledged a 2003 deal did not require on-the-runs to appear in person before a special tribunal.
But he said consideration should be given to deal with victims possibly having to appear, but not the accused.
Secretary of State Peter Hain has been defending the bill in the Commons debate.
It has attracted sustained criticism from both the opposition and some of his own backbenchers.
The legislation will deal with people suspected of terrorism who have not been brought to court and those who have fled prison.
Sinn Fein has repeatedly pressed for them to be able to return to Northern Ireland.
If the legislation is passed, paramilitary fugitives would have their cases heard by a special tribunal, but, if found guilty, would be freed on licence without having to go to jail.
Former Conservative leader Iain Duncan Smith said Mr Hain was proposing to give people who had "run away from their crime" the opportunity to avoid it "completely and utterly".
"People think this is a grubby and reprehensible move on the part of the government and one step too far," he said.
The SDLP leader Mark Durkan denied that the proposals flowed from the Good Friday Agreement, whilst the DUP's William McCrea appeared close to tears whilst talking about close relatives who had lost their lives through terrorism.
The government should consider amendments, Paul Murphy said
He denounced the bill as an "attempt to appease IRA murderers".
Some Labour backbenchers, such as Frank Field and Kate Hoey, also criticised the bill.
Mr Field told MPs that a different standard was being set for those who he referred to as "white Protestant and Catholic terrorists" to that for "black Muslim terrorists".
Kate Hoey asked Mr Hain if the IRA had warned that its war would be on again if the bill was not passed.
Citing the previous Conservative government's decision to enter into secret contact with the IRA, Peter Hain said governments had to take difficult decisions to further the peace process.
He told Ms Hoey that no threat to restart the IRA's war had been made but that the government was "fulfilling past agreements" it had made with the Irish government and Sinn Fein.
North Belfast DUP MP Nigel Dodds said that it was "insulting" to victims for Mr Hain to say the legislation was part of a process to bring closure.
"Has he not heard the victims say they do not want this piece of obnoxious legislation and if he had any decency he would withdraw it straight away," he said.
But, Mr Hain said that at the moment nothing was being done about on-the-runs and that was of "no consolation" to victims.
DUP leader Ian Paisley said there could be no closure for relatives when no action had been taken over the deaths of 202 RUC officers moved into the "cold case" investigations.
"How does he think that this legislation, which is really a wiping of the stone clear, how will that ever close what is in the hearts and the minds and the souls of those people?" he said.
Liberal Democrat spokesman Lembit Opik said it was "perverse" that on-the-runs should be allowed home whilst those exiled by paramilitaries remained outside Northern Ireland.
He said any process of certifying groups for the proposed scheme should be linked to a report by the Independent Monitoring Commission verifying that those groups were allowing exiles to return home.
Speaking earlier, Mr Hain denied the fugitives were getting an easy option.
"It's part of bringing closure to NI's past, just as after the Agreement over 400 paramilitary prisoners were released on licence," he said.
"If they breached the terms of these licences, as some did, they were hauled back in and this could happen to these people who are now outside the reach of the UK jurisdiction."
During Prime Minister's Question Time, Tony Blair said allowing paramilitary fugitives to return will cause a lot of pain and anguish, which is going to have to be dealt with.
Peter Hain denied the legislation was an easy option
The prime minister was responding to a question from DUP MP David Simpson.
He asked Mr Blair what the British people would think if the killers of a female police officer in Bradford last Friday were granted an amnesty.
"What would the British people, or members of his party, think of the prime minister if he offered an amnesty to the murderer of the police officer?" Mr Simpson said.
In response, Mr Blair said he understood "the pain and anguish" the legislation would cause.
"I hope he understands that as a result of the Good Friday Agreement those people convicted of terrorist offences before 1998 have been released, it is now necessary to deal with those who have not been convicted but nonetheless have been suspected of such offences," he said.
"That is the reason for the measures we are bringing forward. I understand the pain and anguish that it causes, but I hope that he understands this is something that has to be dealt with."
The families of four murdered Royal Ulster Constabulary police officers travelled to Downing Street to try to talk the prime minister out of the plans.
One of them, Phyllis Carrothers, said they had left disappointed.
"I'm an RUC widow and I asked Mr Blair, as a family man, to look at a photograph of my three children just prior to my husband's murder and to consider all aspects of the grief and the evacuation from our home and he really just had no answer," she said.