Lawyers representing former soldiers facing prosecution for killings during the Northern Ireland Troubles have called for an independent inquiry.
A London-based firm of solicitors says there are concerns about the decisions to take legal action.
Former soldiers feel they are being unfairly treated, says the firm, Devonshires.
A number of Conservative MPs have called for new legislation to prevent further prosecutions.
The police and Public Prosecution Service (PPS) say cases involving allegations against former soldiers are treated in the same way as all others.
Members of regular regiments of the British Army killed 302 people during the Troubles, more than half of them were civilians.
The first 169 killings were investigated by the Royal Military Police.
The Royal Ulster Constabulary (RUC) then took over responsibility, but did not re-examine those cases.
Critics have questioned the integrity of the investigations into all of the Army killings.
Indeed, an official British government document uncovered by campaign group Relatives for Justice five years ago indicated that an agreement was made to protect soldiers serving in Northern Ireland from prosecution.
Dated 10 July 1972, it said: "The British government should not be inhibited in its campaign by the threat of court proceedings and should therefore be suitably indemnified."
The Legacy Branch of the Police Service of Northern Ireland (PSNI) is re-investigating the Army killings, as part of a review of all deaths during the Troubles.
In 2010, the Saville inquiry found that the Bloody Sunday killings of 13 civilians were unjustified and unjustifiable.
Devonshires says it is currently representing between 10 and 15 former soldiers facing prosecution for a number of killings, including those on Bloody Sunday.
Lawyer Philip Barden said his clients and other former soldiers had serious concerns.
"They do feel that the process is unfair," he said.
"These are soldiers whose shootings were investigated at the time they took place and the then director of public prosecutions took a decision, based upon the evidence that was then available, that no action would be taken against them.
"They've got on with their lives, their memories have faded, and now after, in some cases more than 40 years, they face the prospect of being prosecuted, and they feel that it is very prejudicial for them and they are very concerned by it."
He said the firm had been told there could be as many as 1,000 former soldiers potentially facing prosecution.
The PPS in Northern Ireland said it had no idea where that figure came from.
'Soldiers had immunity'
Devonshires is calling for an independent review of the process to address the concerns of former soldiers.
"Justice must be seen to be done, and I think in these circumstances it would help everybody if someone such as a senior judge were to be instructed by the government to review the processes and procedures that have been put in place," Mr Barden said.
Kate Nash, whose brother, William, was killed on Bloody Sunday, said she was absolutely enraged by Mr Barden's comments.
"The victims of the state in this country have never been on a level playing field when dealing with British justice," she said.
"An inquiry had already found soldiers guilty on Bloody Sunday of firing at victims without fear or panic and perjuring themselves. These soldiers at the Bloody Sunday inquiry had the protection of immunity from prosecution and still didn't tell the truth. It's a disgrace."
'Not a level playing field'
However, DUP MP Sir Jeffery Donaldson said: "I think Kate is right, there isn't a level playing field and I think more money was spent on the Saville inquiry [into Bloody Sunday] than on the investigation of any other killing in the history of Northern Ireland.
"Kate seems to think that the only people who are entitled to access to justice are victims of the state. The IRA were responsible for 60% of the killings in Northern Ireland, the paramilitary terrorists were responsible for over 90% of the killings.
"The problem is that no-one is investigating the unsolved killings committed by the IRA."
The PPS says all of its decisions are reached after careful consideration of the case according to the Code of Prosecutors.
In a statement issued last month, it said: "The Public Prosecution Service only applies the law as it currently stands in Northern Ireland and does so without fear, favour or prejudice."
In response to critics who say army killings were not properly investigated at the time they happened, the lawyer said if that was the case it was not the fault of the former soldiers involved.
"If the state failed to properly investigate matters in the 1970s that should be taken up with the state," he said.
"That's not the responsibility of the individual soldiers who were subject to an investigation, who were told that no action would be taken against them, and have relied upon that."