diff --git a/crates/ruma-state-res/src/lib.rs b/crates/ruma-state-res/src/lib.rs
index 1e7b9a41..e59ecf4b 100644
--- a/crates/ruma-state-res/src/lib.rs
+++ b/crates/ruma-state-res/src/lib.rs
@@ -79,7 +79,7 @@ where
     debug!("{:?}", conflicting);
 
     // The set of auth events that are not common across server forks
-    let mut auth_diff = get_auth_chain_diff(auth_chain_sets)?;
+    let mut auth_diff = get_auth_chain_diff(auth_chain_sets);
 
     // Add the auth_diff to conflicting now we have a full set of conflicting events
     auth_diff.extend(conflicting.values().cloned().flatten().flatten());
@@ -195,16 +195,16 @@ pub fn separate(
 }
 
 /// Returns a Vec of deduped EventIds that appear in some chains but not others.
-pub fn get_auth_chain_diff(auth_chain_sets: Vec<HashSet<EventId>>) -> Result<HashSet<EventId>> {
+pub fn get_auth_chain_diff(auth_chain_sets: Vec<HashSet<EventId>>) -> HashSet<EventId> {
     if let Some(first) = auth_chain_sets.first().cloned() {
         let common = auth_chain_sets
             .iter()
             .skip(1)
             .fold(first, |a, b| a.intersection(b).cloned().collect::<HashSet<EventId>>());
 
-        Ok(auth_chain_sets.into_iter().flatten().filter(|id| !common.contains(id)).collect())
+        auth_chain_sets.into_iter().flatten().filter(|id| !common.contains(id)).collect()
     } else {
-        Ok(HashSet::new())
+        HashSet::new()
     }
 }