The SDLP has said it will not support a plan to block new laws preventing the appointment of Stormont special advisers with serious criminal convictions.
Leader Alasdair McDonnell announced his Stormont Assembly team would not sign a petition of concern which could have defeated the measure, despite branding it "flawed".
He said his MLAs would probably abstain from Monday's vote.
Its proposer, Jim Allister, said victims across Northern Ireland would welcome the decision.
Mr McDonnell said: "We have great difficulty with the bill, it is very flawed."
But he added: "We will not be signing a petition of concern."
A petition of concern is a mechanism whereby a group of MLAs can block legislation.
Sinn Fein, the largest nationalist party, oppose hardline unionist Jim Allister's special advisers bill but need the support of another MLA to veto it.
It would mean anybody with convictions bringing more than five years imprisonment would be barred from becoming a special adviser, although they could appeal.
The legislation has been championed by Ann Travers, a victims campaigner bereaved by IRA violence.
Her sister Mary was shot dead by the IRA almost 30 years ago as they targeted her magistrate father.
She said: "I loved my dad (Tom Travers) and my sister Mary a great deal. Mary did not have a right of appeal unfortunately, she is lying six foot under.
"I will never get that chance again but I just want memory to be upheld and other victims are saying we feel exactly the same."
She added: 'We want to be respected and acknowledged. I am not trying to bash Sinn Fein or ex-prisoners, it was done as a gut reaction for my sister."
Mr Allister's Traditional Unionist Voice (TUV) brought forward the bill after ex-prisoner Mary McArdle was appointed an adviser to a Sinn Fein minister.
She was convicted of the murder of Mary Travers, who was shot as she left Mass with her father in Belfast in 1984.
The bill seeks to ban anyone who has been sentenced to more than five years in prison from taking up a post in the future.
Sinn Fein, which has 29 MLAs, is opposed to the bill and if the party joined forces with the SDLP's 14 MLAs, both parties would be able to secure a petition of concern. Sinn Fein will now need to look elsewhere for support.