The naming of possible suspects at fresh inquests into the 1974 IRA Birmingham pub bombings has been ruled out by a coroner.
Senior coroner Peter Thornton QC said the issue of perpetrators should not be included as he published his written ruling on the scope of the hearings, due to begin later this year.
Bereaved relatives of some of the 21 victims had made strident calls for the widest possible scope in their bid for "truth and justice" ahead of Wednesday's ruling.
Julie Hambleton, whose older sister Maxine died in the double bombings, had said "we may as well not bother having an inquest" if the issue of suspects could not be examined.
In a 15-page ruling, Mr Thornton, the former chief coroner, said: "To permit the identity of perpetrators to be within scope would be seen to be taking on the role of a proxy criminal trial.
"If this were to result in a determination identifying those responsible for the attacks that would, in my judgment, be unlawful."
He added, given the "sheer size and complexity" of any investigation into who may have carried out the attacks, it was not the role of the inquest.
The judge added it would "be invidious for the inquests to attempt to do", what various criminal and case reviews investigations had tried and failed to do over the past 43 years.
He said: "The approach would inevitably be piecemeal and incomplete, mostly reliant upon persons named in books and the press, mostly by journalists."
Mr Thornton added any investigation into the perpetrators was "a task entirely unsuited to the inquest process", given its "limited resources".
He also ruled out the reactions of the emergency services on the night of the bombings, forming any part of the evidence, despite the relatives' asking it be included.
However, Mr Thornton said evidence could be heard on the issue that police may have been tipped off twice about the possibility of a bomb attack, in the run up to the blasts.
Inquiries are also continuing by the coroner's own legal investigation team into whether there is any evidence of a mole within the IRA unit which carried out the bombings.
Mrs Hambleton said: "There is nothing fair about this decision. Without the murderers, our loved ones would not be dead.
"Without the murderers, we would not need to continue to fight the way we have - the way we do - and be traumatised every single day of our lives.
"Having to fight the very people we pay, and who are meant to represent us, to give us the most simple thing.
"What does that say about our Government?"
She added that the relatives of the dead would "continue to fight" for "truth, justice and accountability", saying "the coroner's decision is one decision".
Lawyers for 10 of the families, Northern Ireland-based KRW Law, said in a statement after the rulings that it was "a sad day" for the bereaved.
The solictors added that they would read the decision "very closely".
The statement continued: "Whether the inquest proposed by the coroner satisfies either the demands of the common law or human rights standards and can be read down in accordance with statutory provisions is a point that may require to be tested by way of litigation or by way another form of investigation, such as a statutory inquiry.
"It is clear that from the point of view of our clients in their quest for truth, justice and accountability, today is a sad day and will fuel the bitterness they already have."
The next pre-inquest review will be heard later this month with full hearings set to start in September.