diff --git a/zebra-chain/src/primitives/zcash_primitives.rs b/zebra-chain/src/primitives/zcash_primitives.rs
index 21ffeead609..149ca423cd4 100644
--- a/zebra-chain/src/primitives/zcash_primitives.rs
+++ b/zebra-chain/src/primitives/zcash_primitives.rs
@@ -220,6 +220,8 @@ impl<'a> PrecomputedTxData<'a> {
     /// # Panics
     ///
     /// - If `tx` can't be converted to its `librustzcash` equivalent.
+    /// - If `nu` doesn't contain a consensus branch id convertible to its `librustzcash`
+    ///   equivalent.
     ///
     /// # Consensus
     ///
diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index f7cc72045fc..025bd22881d 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -216,6 +216,10 @@ impl Transaction {
     /// - if called on a v1 or v2 transaction
     /// - if the input index points to a transparent::Input::CoinBase
     /// - if the input index is out of bounds for self.inputs()
+    /// - if the tx contains `nConsensusBranchId` field and `nu` doesn't match it
+    /// - if the tx is not convertible to its `librustzcash` equivalent
+    /// - if `nu` doesn't contain a consensus branch id convertible to its `librustzcash`
+    ///   equivalent
     pub fn sighash(
         &self,
         nu: NetworkUpgrade,
diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index 4738a77bc06..c2460a7101c 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -48,6 +48,14 @@ pub struct SigHasher<'a> {
 
 impl<'a> SigHasher<'a> {
     /// Create a new SigHasher for the given transaction.
+    ///
+    /// # Panics
+    ///
+    /// - If `trans` can't be converted to its `librustzcash` equivalent. This could happen, for
+    ///   example, if `trans` contains the `nConsensusBranchId` field, and `nu` doesn't match it.
+    ///   More details in [`PrecomputedTxData::new`].
+    /// - If `nu` doesn't contain a consensus branch id convertible to its `librustzcash`
+    ///   equivalent.
     pub fn new(
         trans: &'a Transaction,
         nu: NetworkUpgrade,