AN overhaul of the Fatal Accident Inquiry system has been criticised by victims' families and legal experts for failing to bring an end to the delays that can cause years of distress to relatives.

The Scottish Government has confirmed planned legislation will not speed up decisions over Fatal Accident Inquiries when a criminal investigation has been launched.

The move has come under fire from lawyers and union leaders, who believe ministers should be addressing concerns about the "lottery" in deciding on inquiries. Relatives say they have been left "in limbo" by the "torturous" process of FAIs.

The Government consultation over an FAI shake-up comes a year after a Member's Bill that sought to speed up the system in the wake of criticism over delays in establishing whether there will be inquiries into major incidents. In Scotland, an FAI is not instructed until a decision has been made whether to proceed with a criminal case.

However, Thompsons Scotland, the legal firm that has represented a series of bereaved families who feel let down by the system, says any conflict with criminal issues can be avoided by taking a leaf out the English Coroner's Court process, where an inquiry can be opened and then adjourned, if deemed necessary.

Any inquiry started while the prosecution process is continuing could then consider matters that will not be before the criminal courts.

Patrick Maguire, of Thompsons, said criminal inquiries and FAIs were "as important as each other". He added: "For families to move on, they need to understand what happened, but what families actually want is to ensure they have not suffered for no reason at all."

Caroline Doyle, whose 57-year-old father Raymond died in a North Sea helicopter crash in 2009, said something should be done to speed up the process. She and relatives of the other 15 men who died in the tragedy had to wait five years for a Fatal Accident Inquiry to conclude the disaster could have been prevented.

She said: "It was far too long to wait, because you can't move forward. You always have that there, hanging over your head, and you don't know what has happened to your loved one. It is torturous.

"There are a lot of things we found out at the FAI that we could have been told prior to that. When we finally got the sheriff's determination the big bone of contention was the Crown had decided not to prosecute. We had a really bad experience and were quite bitter."

There are only about 50 to 70 FAIs per year but more than 13,000 deaths are reported to procurators-fiscal annually. Thompsons data from 2012 reveals that, despite an FAI for a death at work being mandatory by law, in 29 per cent of cases no such investigation is carried out.

Under the new proposals, the Lord Advocate can still decide it is unnecessary to hold an FAI if the circumstances of the death have been sufficiently established in criminal proceedings.

The proposals also keep in place strict limits over the release of documentary evidence to families while criminal investigations are proceeding. It proposes their release only where it does not contravene legal obligations, such as the Data Protection Act 1998, and in any case only after any criminal proceedings are concluded.

Pat Rafferty, secretary of the union Unite Scotland, said: "The delays in FAIs are totally unacceptable. The Scottish Government has not been listening to those who say there has to be provisions to reduce the unacceptable delays Fatal Accident Inquiries currently experience."

In a letter to Justice Secretary Kenny MacAskill earlier this year, Lord Cullen, who carried out a review of the FAI system in 2009, did not recommend time limits on the conclusion of FAIs "because of the diversity and potential complexity of the cases, and because other investigations or proceedings may have to be completed first".

A Scottish Government spokeswoman said: "The consultation is about a number of aspects of the FAI process, but in terms of speeding up the process, that will not change.

"It will still be the case that investigations by other regulatory bodies need to be completed, then decisions taken on whether criminal proceedings are appropriate before any FAI can be instructed by the Crown. It will streamline the process for different types of deaths.

"Investigations by other regulatory bodies need to be completed and decisions taken on whether criminal proceedings are appropriate before any FAI can be instructed by the Crown.

"In addition, investigations into complex incidents, such as helicopter crashes, tend to take a long time to establish the cause of the accident.

"While these are not factors that can be influenced, our proposals will mean the FAI process becomes much more streamlined and effective once it is instructed."