Guillaume Boulle rehabilitated Joan of ArcFor more information, see: Rehabilitation trial of Joan of Arc
Fighting in the Hundred Years' War continued for over two decades following Joan's death, but the tide had turned and the impetus to the French cause given by Joan's career would not be stemmed.
Although the English staged a rival coronation in Paris of the young Henry VI, the effect on public opinion was, if anything, negative. The English suffered some military reversals around Paris the following year and negotiations between the Duke of Burgundy and Charles VII were begun shortly thereafter. These negotiations eventually resulted in the Treaty of Arras (1435) which ended the Anglo-Burgundian alliance.
Paris fell to the French in 1437 and, by 1450, the English were routed from their remaining strongholds in Normandy. The final act in the Hundred Years' War was played out at Castillon in July of 1453 when the Engish were finally expelled from Aquitaine, their last remaining foothold in France. Meanwhile, the process leading to Joan's rehabilitation had already begun.
In 1449, the city of Rouen opened its gates to Charles and Dunois and the trial records became available. With the war drawing to a close, early the following year (15 February 1450), Charles appointed Guillaume Boulle to study the records to ascertain the facts about the original Trial.
Boulle took depositions from several participants in the Trial, including Guillaume Manchon and Beaupere. All but one testified to judicial bias, English pressure and numerous procedural violations. Boulle then drew up a summary and delivered it to Charles.
In February of 1452, Cardinal d'Estouteville, Papal legate to France, met with Charles and contacted Inquisitor General Jean Brehal concerning the matter. Later that year, in May, Brehal produced a critique of the original Trial consisting of 12 articles, including the charge that Cauchon was biased and that he was not legally empowered to conduct the Trial.
Finally, in response to a petition from Joan's mother, Pope Calixtus III authorized an inquiry into the original Trial. On November 7, 1455, a Papal commission headed by Jean Jouvenel des Ursins, the Archbishop of Reims, began its work with hearings in Paris.
The Commission took testimony from over a hundred witnesses, including noted jurists and theologians, those who were present at the original Trial, as well as her childhood friends and acquaintences who were questioned about her piety and virtue, her activities as a child, and other matters which had been examined at the Trial. The original list of 12 articles was expanded to 27 points and submitted to theologians and canon law experts who pronounced in favor of Joan.
After the verdict of the nullification Trial was released, the original 12 articles of indictment were formally read and termed "iniquitous, false, prepared in a lying manner without reference to Joan's confessions".