diff --git a/combo/apps/maps/static/js/combo.map.js b/combo/apps/maps/static/js/combo.map.js
index 2380cecc..2dd64a9f 100644
--- a/combo/apps/maps/static/js/combo.map.js
+++ b/combo/apps/maps/static/js/combo.map.js
@@ -150,7 +150,7 @@ $(function() {
         disable_layer: function(slug) {
           var layer = this.geojson_layers[slug];
           var group = this.clustered_markers || this;
-          if (layer) {
+          if (layer && layer.leaflet_layer) {
             group.removeLayer(layer.leaflet_layer);
           }
         },
@@ -158,7 +158,7 @@ $(function() {
         enable_layer: function(slug) {
           var layer = this.geojson_layers[slug];
           var group = this.clustered_markers || this;
-          if (layer) {
+          if (layer && layer.leaflet_layer) {
             group.addLayer(layer.leaflet_layer);
           }
         },