An urgent review of fatal accident inquiries into deaths in custody has been demanded by campaigners.
Campaigners warn the law could be challenged in Europe
It follows complaints from a number of bereaved relatives who were dissatisfied with way they work.
The concerns raised have prompted wider questions over the Fatal Accidents and Sudden Deaths Inquiry (Scotland) Act of 1976.
The Scottish Human Rights Centre is now urging the Scottish Executive to examine the legislation.
It has been suggested the fatal accidents and sudden deaths legislation breaches human rights by failing to investigate deaths in custody effectively.
Families of people who have died whilst in custody have said sweeping changes are needed to the system.
An FAI into the death of 35-year-old April Adam, who hanged herself in Cornton Vale two years ago, found that no-one was negligent.
The Adam family are now seeking a judicial review of the sheriff's conclusions from the inquiry into her death.
Her friend Doreen Evans said: "A fatal accident inquiry into a death in prison, you would think they were looking to see what went wrong, who was at fault, were the strategies implemented?"
The Scottish Human Rights Centre (SHRC) has said the executive should consider the legislation before it can be tested in the European court.
It warned the executive should move quickly or a legal challenge would be inevitable.
SHRC lawyer John Scott said: "That would be an expensive way, a lengthy way of doing it.
"The families would feel, I think, worse because the executive has been forced into doing it, rather than acknowledging that there is a problem here, that families aren't happy and that they are entitled to more answers than they are getting."