diff --git a/src/sign.rs b/src/sign.rs
index ba6d074..7fa9e9f 100644
--- a/src/sign.rs
+++ b/src/sign.rs
@@ -12,13 +12,20 @@ use crate::utils;
 pub fn command(key_path: PathBuf, rev: String) -> Result<()> {
     let repo = utils::open_repository()?;
     for (path, secret_key) in utils::get_secret_keys(key_path)? {
-        let tree_oid = sign(&repo, &secret_key, &rev)?;
-        let signed_object = {
-            let tree_sig = utils::TreeSignature::load_oid(&repo, tree_oid)?;
-            tree_sig.dereference()?
-        };
+        let signed_object = repo
+            .revparse_single(&rev)
+            .context("Failed to look-up object to sign")?
+            .id();
         let key_fingerprint = secret_key.public_key()?.fingerprint()?;
         let reference = utils::craft_signature_reference(key_fingerprint, signed_object);
+        if utils::revparse_single_ok_or_else(&repo, &reference, |_| Ok(true), || Ok(false))? {
+            println!("Signature already exists with key:");
+            println!("  - {}", path.display());
+            println!("Signature stored under:");
+            println!("  - {reference}");
+            continue;
+        }
+        let tree_oid = sign(&repo, &secret_key, &rev)?;
         repo.reference(
             &reference, tree_oid,
             // references to signatures are non-deterministic,