diff --git a/app/controllers/aspect_memberships_controller.rb b/app/controllers/aspect_memberships_controller.rb
index 69b6c07d9..6bb565d1d 100644
--- a/app/controllers/aspect_memberships_controller.rb
+++ b/app/controllers/aspect_memberships_controller.rb
@@ -17,7 +17,7 @@ class AspectMembershipsController < ApplicationController
     @contact = current_user.contact_for(Person.where(:id => @person_id).first)
     membership = @contact ? @contact.aspect_memberships.where(:aspect_id => @aspect_id).first : nil
 
-    if membership && membership.destroy 
+    if membership && membership.destroy
         @aspect = membership.aspect
         flash.now[:notice] = I18n.t 'aspect_memberships.destroy.success'
 
@@ -76,4 +76,8 @@ class AspectMembershipsController < ApplicationController
     render :text => response_hash.to_json
   end
 
+  rescue_from ActiveRecord::RecordNotUnique do
+    render :text => "Duplicate record rejected.", :status => 400
+  end
+
 end
diff --git a/spec/controllers/aspect_memberships_controller_spec.rb b/spec/controllers/aspect_memberships_controller_spec.rb
index 7d4cb8c5c..b190f728d 100644
--- a/spec/controllers/aspect_memberships_controller_spec.rb
+++ b/spec/controllers/aspect_memberships_controller_spec.rb
@@ -13,7 +13,7 @@ describe AspectMembershipsController do
     @contact = alice.contact_for(bob.person)
     alice.getting_started = false
     alice.save
-    sign_in :user, alice 
+    sign_in :user, alice
     @controller.stub(:current_user).and_return(alice)
     request.env["HTTP_REFERER"] = 'http://' + request.host
   end
@@ -62,6 +62,13 @@ describe AspectMembershipsController do
       flash[:error].should_not be_empty
     end
 
+    it 'does not 500 on a duplicate key error' do
+      params = {:format => 'js', :person_id => @person.id, :aspect_id => @aspect0.id}
+      post :create, params
+      post :create, params
+      response.status.should == 400
+    end
+
     context 'json' do
       it 'returns a list of aspect ids for the person' do
         post :create,