diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index 0d2b52b9f..f241df6da 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -1092,8 +1092,8 @@ def verify_slashable_vote_data(state: BeaconState, vote_data: SlashableVoteData)
 
     return bls_verify_multiple(
         pubkeys=[
-            bls_aggregate_pubkey([state.validators[i].pubkey for i in vote_data.custody_bit_0_indices]),
-            bls_aggregate_pubkey([state.validators[i].pubkey for i in vote_data.custody_bit_1_indices]),
+            bls_aggregate_pubkey([state.validator_registry[i].pubkey for i in vote_data.custody_bit_0_indices]),
+            bls_aggregate_pubkey([state.validator_registry[i].pubkey for i in vote_data.custody_bit_1_indices]),
         ],
         messages=[
             hash_tree_root(AttestationDataAndCustodyBit(vote_data.data, False)),