From: Rabbi Moshe Sofer
To: Rabbi Avraham
The Napoleonic-era Consistoire of Westphalia issued a ruling permitting kitniyos consumption on Pesach. The Chasam Sofer emphatically invalidates this ruling, arguing that the kitniyos prohibition functions as a seyag to a Torah law that no court can annul.
Source: Shu"t Chasam Sofer OC §122