diff --git a/src/jimgw/prior.py b/src/jimgw/prior.py
index 7577ffd7..384eb8e5 100644
--- a/src/jimgw/prior.py
+++ b/src/jimgw/prior.py
@@ -263,7 +263,13 @@ def sample(
         return self.add_name(jnp.stack([theta, phi, mag], axis=1).T)
 
     def log_prob(self, x: dict[str, Float]) -> Float:
-        return jnp.log(x[self.naming[2]] ** 2 * jnp.sin(x[self.naming[0]]))
+        mag = x[self.naming[2]]
+        output = jnp.where(
+            (mag > 1) | (mag < 0),
+            jnp.zeros_like(0) - jnp.inf,
+            jnp.log(mag**2 * jnp.sin(x[self.naming[0]])),
+        )
+        return output
 
 
 @jaxtyped