diff --git a/evm/Cargo.toml b/evm/Cargo.toml
index 25251daa..63f4ec0c 100644
--- a/evm/Cargo.toml
+++ b/evm/Cargo.toml
@@ -33,7 +33,6 @@ rand_chacha = "0.3.1"
 rlp = "0.5.1"
 rlp-derive = "0.1.0"
 serde = { version = "1.0.144", features = ["derive"] }
-
 static_assertions = "1.1.0"
 hashbrown = { version = "0.12.3" }
 tiny-keccak = "2.0.2"
diff --git a/plonky2/src/gates/gate.rs b/plonky2/src/gates/gate.rs
index 0bafb8a7..1dbc4f57 100644
--- a/plonky2/src/gates/gate.rs
+++ b/plonky2/src/gates/gate.rs
@@ -270,6 +270,7 @@ pub struct PrefixedGate<F: RichField + Extendable<D>, const D: usize> {
 
 /// A gate's filter designed so that it is non-zero if `s = row`.
 fn compute_filter<K: Field>(row: usize, group_range: Range<usize>, s: K, many_selector: bool) -> K {
+    debug_assert!(group_range.contains(&row));
     group_range
         .filter(|&i| i != row)
         .chain(many_selector.then_some(UNUSED_SELECTOR))