diff --git a/lib/blacklight_advanced_search/redirect_legacy_params_filter.rb b/lib/blacklight_advanced_search/redirect_legacy_params_filter.rb
index dbb8ba9..153aa27 100644
--- a/lib/blacklight_advanced_search/redirect_legacy_params_filter.rb
+++ b/lib/blacklight_advanced_search/redirect_legacy_params_filter.rb
@@ -40,8 +40,8 @@ def self.before(controller)
       end
 
       if legacy_converted
-        controller.send(:redirect_to, params, :status => :moved_permanently)
+        controller.send(:redirect_to, params.to_unsafe_h, :status => :moved_permanently)
       end
     end
   end
-  end
+end