The 78-year-old victim of lottery winning rapist Iorworth Hoare won the right on Tuesday to claim damages from him for the ordeal he put her through 20 years ago.
There should be a hearing soon to decide the level of compensation she should receive, the High Court ruled.
The victim, a former teacher known only as Mrs A, was subjected to a brutal sex attack by Hoare in broad daylight as she walked in a park in Leeds in 1988. She was 59 at the time.
Hoare, who the courts have been told was guilty of a series of sexual assaults on women including at least two rapes, was jailed for life in 1989 for the attempted rape of Mrs A. The judge who jailed him said he was "a risk to all women".
However, Mrs A did not attempt to sue him at the time because he had no money and any judgment would have been worthless.
But in 2004, while out on day release from prison, Hoare bought a national lottery ticket and won 7.2 million pounds. Mrs A then attempted to launch a damages claim for assault and battery and psychiatric injury.
Her claim was thrown out by the High Court and Court of Appeal on the basis that it came outside the six years allowed for such claims to be brought.
But in a landmark ruling earlier this year, the House of Lords ruled that the case should be re-considered by the High Court.
On Tuesday, Mr Justice Coulson found in her favour and ruled that she could sue Hoare, dubbed the "Lotto rapist" by the press, for damages.
Coulson said while there were some reasons to back arguments put forward by Hoare's lawyers to stop the claim, the factors supporting Mrs A's case were "more numerous and of significantly greater weight".
Mrs A, who says she still suffers from nightmares and says the attack ruined her life forever, received 5,000 pounds from the Criminal Injuries Compensation Board for her ordeal.
Hoare, now 53, was freed on licence in 2004 after 16 years behind bars, and was able to spend his winnings under an assumed name.
