diff --git a/lighthouse/db/src/stores/beacon_block_store.rs b/lighthouse/db/src/stores/beacon_block_store.rs
index 615c8fbe7..21cd2abc8 100644
--- a/lighthouse/db/src/stores/beacon_block_store.rs
+++ b/lighthouse/db/src/stores/beacon_block_store.rs
@@ -120,6 +120,19 @@ mod tests {
         assert_eq!(store.get_serialized_block(hash).unwrap().unwrap(), ssz);
     }
 
+    #[test]
+    fn test_get_none_serialized_block() {
+        let db = Arc::new(MemoryDB::open());
+        let store = BeaconBlockStore::new(db.clone());
+
+        let ssz = "some bytes".as_bytes();
+        let hash = &Hash256::from("some hash".as_bytes()).to_vec();
+        let other_hash = &Hash256::from("another hash".as_bytes()).to_vec();
+
+        db.put(DB_COLUMN, other_hash, ssz).unwrap();
+        assert_eq!(store.get_serialized_block(hash).unwrap(), None);
+    }
+
     #[test]
     fn test_block_exists() {
         let db = Arc::new(MemoryDB::open());
@@ -160,6 +173,31 @@ mod tests {
         assert!(!db.exists(DB_COLUMN, hash).unwrap());
     }
 
+    #[test]
+    fn test_invalid_block_at_slot() {
+        let db = Arc::new(MemoryDB::open());
+        let store = BeaconBlockStore::new(db.clone());
+
+        let ssz = "definitly not a valid block".as_bytes();
+        let hash = &Hash256::from("some hash".as_bytes()).to_vec();
+
+        db.put(DB_COLUMN, hash, ssz).unwrap();
+        assert_eq!(store.block_at_slot(hash, 42), Err(BeaconBlockAtSlotError::InvalidBeaconBlock));
+    }
+
+    #[test]
+    fn test_unknown_block_at_slot() {
+        let db = Arc::new(MemoryDB::open());
+        let store = BeaconBlockStore::new(db.clone());
+
+        let ssz = "some bytes".as_bytes();
+        let hash = &Hash256::from("some hash".as_bytes()).to_vec();
+        let other_hash = &Hash256::from("another hash".as_bytes()).to_vec();
+
+        db.put(DB_COLUMN, hash, ssz).unwrap();
+        assert_eq!(store.block_at_slot(other_hash, 42), Err(BeaconBlockAtSlotError::UnknownBeaconBlock));
+    }
+
     #[test]
     fn test_block_store_on_memory_db() {
         let db = Arc::new(MemoryDB::open());
diff --git a/lighthouse/db/src/stores/validator_store.rs b/lighthouse/db/src/stores/validator_store.rs
index 1970cf4fd..a802a0d0e 100644
--- a/lighthouse/db/src/stores/validator_store.rs
+++ b/lighthouse/db/src/stores/validator_store.rs
@@ -98,7 +98,7 @@ mod tests {
 
         assert_eq!(public_key_at_index, public_key.as_bytes());
     }
-
+    
     #[test]
     fn test_get_public_key_by_index() {
         let db = Arc::new(MemoryDB::open());
@@ -134,6 +134,20 @@ mod tests {
         assert_eq!(public_key_at_index, None);
     }
 
+    #[test]
+    fn test_get_invalid_public_key() {
+        let db = Arc::new(MemoryDB::open());
+        let store = ValidatorStore::new(db.clone());
+
+        let key = store.get_db_key_for_index(&KeyPrefixes::PublicKey, 42);
+        db.put(DB_COLUMN, &key[..], "cats".as_bytes()).unwrap();
+
+        assert_eq!(
+            store.get_public_key_by_index(42),
+            Err(ValidatorStoreError::DecodeError)
+        );
+    }
+
     #[test]
     fn test_validator_store_put_get() {
         let db = Arc::new(MemoryDB::open());
@@ -169,18 +183,4 @@ mod tests {
                 .is_none()
         );
     }
-
-    #[test]
-    fn test_validator_store_bad_key() {
-        let db = Arc::new(MemoryDB::open());
-        let store = ValidatorStore::new(db.clone());
-
-        let key = store.get_db_key_for_index(&KeyPrefixes::PublicKey, 42);
-        db.put(DB_COLUMN, &key[..], "cats".as_bytes()).unwrap();
-
-        assert_eq!(
-            store.get_public_key_by_index(42),
-            Err(ValidatorStoreError::DecodeError)
-        );
-    }
 }