diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5ef9c799..5dbb335a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,5 @@
 ## Pending
+- MarlinPC's `supported_degree` fix.
 
 ### Breaking changes
 
diff --git a/src/marlin/marlin_pc/data_structures.rs b/src/marlin/marlin_pc/data_structures.rs
index 2e4581db..37e075db 100644
--- a/src/marlin/marlin_pc/data_structures.rs
+++ b/src/marlin/marlin_pc/data_structures.rs
@@ -88,7 +88,7 @@ impl<E: PairingEngine> PCCommitterKey for CommitterKey<E> {
     }
 
     fn supported_degree(&self) -> usize {
-        self.powers.len()
+        self.powers.len() - 1
     }
 }