She was practically teetotal. Eileen O'Hara barely drank; a glass of wine at Christmas perhaps, no more. Some found that hard to believe: by 64, she was crippled with cirrhosis of the liver.

"She was really embarrassed," her eldest daughter, Roseleen Kennedy, said yesterday. "She felt like she was being accused of being an alcoholic."

Mrs O'Hara was no drunk. Nor could she be. As a child she developed rheumatic fever, sparking a heart disease that was to plague her entire adult life and make it impossible for her to overindulge.

The cirrhosis wasn't from drink. It was from hepatitis C, a virus her family know she must have caught from contaminated blood she was given in one of two operations on her heart. Hepatitis and its consequences, including liver disease, was to kill Mrs O'Hara. She died in 2003, aged 72, never understanding how she came to get the virus and the resulting cirrhosis, both of which carried a stigma she hated.

"It angered her," said Mrs Kennedy, a 42-year-old teacher from Glasgow. "It was the only thing that angered her. She was a wonderful woman and she never complained about anything else."

Eighteen months ago, Mrs Kennedy and other family members demanded a fatal accident inquiry into Mrs O'Hara's death. They were refused by the Lord Advocate, Elish Angiolini. A day later Andy Kerr, the then Labour health minister, ruled out a public inquiry into all deaths caused by infected blood products given to patients, not least haemophiliacs, in the 1970s and 1980s.

Yesterday, a Court of Session judge overturned Ms Angiolini's decision, instructing her to carry out a judicial review into the death of both Mrs O'Hara and another victim of hepatitis C, David Black, a Baptist minister who died the same year, aged 66.

Lord Mackay of Drumadoon said Ms Angiolini had failed to respect the human rights of Mrs O'Hara and Mr Black. The SNP-led Scottish Government has already promised a public inquiry into how hundreds of people - perhaps more - were infected. Lord Mackay's decision means that inquiry will have teeth.

It also marks a historic and humiliating first for the Crown Office. Never before has a decision by the Lord Advocate on whether or not to investigate a death been overturned by the courts.

Nicola Sturgeon, the Health Secretary who has championed the cause of hepatitis victims, said ministers and the Lord Advocate would look at the Mackay findings in detail. No date has been set for the judicial inquiry.

"I'm delighted that at last we get an opportunity to find answers to the questions we've had for many years," said another of Mrs O'Hara's daughters, Annette, 39, yesterday. It hasn't been easy on the family. "It's been a struggle," said Ms O'Hara, from Bishopbriggs. "It has been very difficult at times, but luckily we are a close-knit family and we've been able to support each other."

Both daughters - along with another sister and a brother - don't have far to look for inspiration: their mother. "She's pushing us," Annette said yesterday, looking heavenwards. "I think it's keeping us going."

Their campaign has come at a cost. The Crown Office refused to allow court costs to be capped. The O'Hara family faced significant financial problems if they had lost their case. They were supported, true. The Scottish Forum of the Haemophilia Society - hundreds of whose members were given infected blood - put up half the overall court bill of £100,000. The Scottish Government will now have to pay those costs.

Mr Black, the minister who died, had suffered from haemophilia, a manageable blood condition.

A charismatic Christian who once led a movement called Scottish Churches Renewal, Mr Black had borne his illness with dignity. The hepatitis he contracted destroyed his liver. He was given a transplanted organ until it, too, succumbed to cancer caused by the virus.

The lawyer leading the case was Frank Maguire of Thompsons Solicitors.

"The Lord Advocate, one of whose central roles is to uphold the right to life and investigate deaths, has been told by a Court of Session judge that she's got it wrong, that she's acted unlawfully," Mr Maguire said yesterday. Authorities did not want to see FAIs. "The Lord Advocate," he said, "has resisted it and resisted it and resisted it."

Some think they know why. Haemophiliacs are now deeply suspicious about the motives of governments north and south of the border.

Philip Dolan, of their society's Scottish Forum, yesterday suggested the phones of members of his organisation had been tapped. There are something like 4000 people who received blood transfusions in the decades when campaigners believed blood products were infected. Many of them may have hepatitis C and not know it. A successful judicial review could see them sue the NHS.

Compensation, however, was not the motivation for the O'Haras. "It's about answers," said Mrs Kennedy yesterday. Her mother - "a wonderful woman" - was robbed of her final years, only knowing three of her seven grandchildren. Exhausted, she didn't have the strength to enjoy her family as much as she would have loved.

"She was tired, very lethargic with low energy," Ms O'Hara added. "Her stomach was swollen."

The worst humiliation came when Mrs O'Hara, from Balornock in Glasgow, was in Stobhill Hospital in her last years. "They wrote Hep C on the front of her medical notes," Annette said. "She had worked at the hospital and knew people who would be passing on the notes."

Mrs O'Hara was diagnosed in 1995, four years after her last operation. "She would have been infected for at least that long," Mrs Kennedy said. For those years her entire family was at risk of the highly infectious virus, which is usually transmitted through body fluids. Her daughters borrowed her earrings, even mopped up blood. Luckily they haven't contracted the disease.

There was no effort made by the NHS to trace people who were given potentially risky transfusions, campaigners warn.

Scotland had been slower than England to introduce safety measures for blood products, which were only screened for hepatitis C from 1991. England, too, has been quicker to look into questions over contaminated blood. A private inquiry, chaired by Lord Archer of Sandwell, is due to report.

The government, Mrs Kennedy says, has been indifferent to their claims, dodging the issue. Amid all the family's questions about what happened to their mother, one stands out. What has it had to hide?

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