diff --git a/src/pyrecest/smoothers/sliding_window_manifold_mean_smoother.py b/src/pyrecest/smoothers/sliding_window_manifold_mean_smoother.py
index 1ad9c2a946..cefaf149d0 100644
--- a/src/pyrecest/smoothers/sliding_window_manifold_mean_smoother.py
+++ b/src/pyrecest/smoothers/sliding_window_manifold_mean_smoother.py
@@ -6,8 +6,9 @@
 from functools import partial
 from operator import index as operator_index
 
+from pyrecest.backend import all as backend_all
 from pyrecest.backend import any as backend_any
-from pyrecest.backend import asarray, concatenate, ndim, stack, sum
+from pyrecest.backend import asarray, concatenate, isfinite, ndim, stack, sum
 from pyrecest.distributions import (
     AbstractHypercylindricalDistribution,
     AbstractHyperhemisphericalDistribution,
@@ -92,6 +93,8 @@ def __init__(
             self.window_weights = asarray(window_weights).reshape(-1)
             if self.window_weights.shape[0] != self.window_size:
                 raise ValueError("window_weights must have length window_size.")
+            if not bool(backend_all(isfinite(self.window_weights))):
+                raise ValueError("window_weights must be finite.")
             if backend_any(self.window_weights < 0):
                 raise ValueError("window_weights must be non-negative.")
             if sum(self.window_weights) <= 0:
diff --git a/tests/smoothers/test_sliding_window_manifold_mean_smoother_nonfinite_weights.py b/tests/smoothers/test_sliding_window_manifold_mean_smoother_nonfinite_weights.py
new file mode 100644
index 0000000000..3be7fc452e
--- /dev/null
+++ b/tests/smoothers/test_sliding_window_manifold_mean_smoother_nonfinite_weights.py
@@ -0,0 +1,26 @@
+import unittest
+
+import numpy as np
+from pyrecest.backend import array
+from pyrecest.smoothers import SlidingWindowManifoldMeanSmoother
+
+
+class SlidingWindowManifoldMeanSmootherNonfiniteWeightsTest(unittest.TestCase):
+    def test_rejects_nonfinite_window_weights(self):
+        invalid_weight_vectors = (
+            array([1.0, np.nan, 1.0]),
+            array([1.0, np.inf, 1.0]),
+            array([1.0, -np.inf, 1.0]),
+        )
+
+        for window_weights in invalid_weight_vectors:
+            with self.subTest(window_weights=window_weights):
+                with self.assertRaisesRegex(ValueError, "finite"):
+                    SlidingWindowManifoldMeanSmoother(
+                        window_size=3,
+                        window_weights=window_weights,
+                    )
+
+
+if __name__ == "__main__":
+    unittest.main()