diff --git a/zcash_primitives/src/transaction/components/transparent.rs b/zcash_primitives/src/transaction/components/transparent.rs
index f3ee53802..6b1261be7 100644
--- a/zcash_primitives/src/transaction/components/transparent.rs
+++ b/zcash_primitives/src/transaction/components/transparent.rs
@@ -175,7 +175,7 @@ pub mod testing {
     ];
 
     prop_compose! {
-        pub fn arb_outpoint()(hash in prop::array::uniform32(1u8..), n in 1..100u32) -> OutPoint {
+        pub fn arb_outpoint()(hash in prop::array::uniform32(0u8..), n in 0..100u32) -> OutPoint {
             OutPoint::new(hash, n)
         }
     }
diff --git a/zcash_primitives/src/transaction/components/tze.rs b/zcash_primitives/src/transaction/components/tze.rs
index 06ce1e616..4df728775 100644
--- a/zcash_primitives/src/transaction/components/tze.rs
+++ b/zcash_primitives/src/transaction/components/tze.rs
@@ -237,7 +237,7 @@ pub mod testing {
     use super::{Authorized, Bundle, OutPoint, TzeIn, TzeOut};
 
     prop_compose! {
-        pub fn arb_outpoint()(txid in arb_txid(), n in 1..100u32) -> OutPoint {
+        pub fn arb_outpoint()(txid in arb_txid(), n in 0..100u32) -> OutPoint {
             OutPoint::new(txid, n)
         }
     }