diff --git a/app/models/issue.rb b/app/models/issue.rb
index f628f8e..40b0475 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -135,7 +135,10 @@ class Issue < ActiveRecord::Base
     end
   end
   
-  def before_save  
+  def before_save
+
+    self.assigned_to = nil if IssueStatus.find(status_id).is_closed
+    
     if @current_journal
       # attributes changes
       (Issue.column_names - %w(id description)).each {|c|