diff --git a/pyNN/common/populations.py b/pyNN/common/populations.py
index 398bac925..6f3b5060f 100644
--- a/pyNN/common/populations.py
+++ b/pyNN/common/populations.py
@@ -1144,7 +1144,7 @@ def __getitem__(self, index):
             pindex = boundaries[1:].searchsorted(index, side='right')
             return self.populations[pindex][index - boundaries[pindex]]
         elif isinstance(index, (slice, tuple, list, numpy.ndarray)):
-            if isinstance(index, slice) or index.dtype == bool:
+            if isinstance(index, slice) or (hasattr(index, "dtype") and index.dtype == bool):
                 indices = numpy.arange(self.size)[index]
             else:
                 indices = numpy.array(index)