Papers calling for a judicial review of how hundreds of people became infected with Hepatitis C have been lodged at the Court of Session in Edinburgh.
Patients were infected through contaminated blood
About 550 patients were infected with the virus via contaminated blood in Scotland in the 1970s and 1980s.
Victims' lawyers want the Scottish Executive to explain how they managed to contract the virus and to force the Lord Advocate to hold an inquiry.
An executive spokesman expressed doubts over what an inquiry would achieve.
The legal move is the latest step in a 14-year fight to find answers but campaigners are not optimistic they will succeed.
Solicitor advocate Frank Maguire confirmed the action against Lord Advocate Colin Boyd QC and Health Minister Andy Kerr.
Mr Maguire claims the Lord Advocate and Mr Kerr were in breach of Article 2 of the European Court of Human Rights as they failed to hold a prompt inquiry into the deaths of people who contracted Hep C.
He said: "The purpose of such an inquiry is for relatives to have a full explanation as to why a loved one died, to expose the full facts surrounding their death, bring to light any negligent or discreditable conduct and to reassure the public that it will not happen again."
He added that it was not up to the Lord Advocate or the health minister to decide whether or not to hold an inquiry, insisting they were obliged to do so under Article 2.
The executive spokesman said: "The Crown Office are doing their own investigation so that the Lord Advocate can decide whether or not it is in the public interest for a fatal accident inquiry to take place."
He added: "We are not convinced that a public inquiry would be able to establish responsibility for the events that took place or that there are real lessons to be learnt that have not already been learnt."
Bruce Norvelle, from the Black Isle, is one of the victims and he fears any decision will come too late for those affected.
"The arguments are based on fundamental principles of human rights law," he said.
"Every individual who died as a result of government action has the right to an inquiry into that death and that is what the lawyers are trying to establish.
"I started this campaign 14 years ago, not on my own but with a load of other guys, most of whom aren't around anymore - they're all dead.
"My biggest fear has always been in this, that we would get justice eventually, it's just that would be none of us left to actually hear it."
In 2003, the executive led the UK in agreeing to make compassionate payments to Hep C victims of up to £40,000.
However, patients have described the sum on offer as derisory.
Philip Dolan, chairman of the Scottish Haemophilia Groups, said sufferers and relatives had lost patience with the judicial process.
He also called on MSPs who backed the campaign when it was presented to the petitions committee six years ago to use their increased influence to help campaigners.
Mr Dolan said: "MSPs of all parties signed it, including Cathy Jamieson, now justice minister, Hugh Henry, now deputy justice minister and Margaret Curran, now minister for parliament.
"If they felt strongly enough to sign our petition back then, why can't they take action now they are the ministers with responsibility for the actions of the Crown Office?"