diff --git a/app/models/query.rb b/app/models/query.rb
index e18b06805..3313248c4 100644
--- a/app/models/query.rb
+++ b/app/models/query.rb
@@ -1065,7 +1065,7 @@ class Query < ActiveRecord::Base
   end
 
   def display_type=(type)
-    unless type || self.available_display_types.include?(type)
+    unless type && self.available_display_types.include?(type)
       type = self.available_display_types.first
     end
     options[:display_type] = type
diff --git a/test/unit/query_test.rb b/test/unit/query_test.rb
index 1591e985e..e4ac5bd6f 100644
--- a/test/unit/query_test.rb
+++ b/test/unit/query_test.rb
@@ -2880,4 +2880,18 @@ class QueryTest < ActiveSupport::TestCase
 
     assert_equal 1, query.issue_count
   end
+
+  def test_display_type_should_accept_known_types
+    query = ProjectQuery.new(:name => '_')
+    query.display_type = 'list'
+
+    assert_equal 'list', query.display_type
+  end
+
+  def test_display_type_should_not_accept_unknown_types
+    query = ProjectQuery.new(:name => '_')
+    query.display_type = 'invalid'
+
+    assert_equal 'board', query.display_type
+  end
 end