title: Find committer of a force push on github
body: <p>In our project (which is hosted on GitHub), someone accidentally force-pushes master every once in a while. No one is aware if doing so, and I would like to find out who does it and what sort of misconfigured tool or bad habit is behind it.</p>
  
  <p>So the question is, how to identify the user who made the force push? When I pull I see something like this:</p>
  
  <pre><code># git pull --prune
  (.....)
   + 4c0d44c...138b9ed master     -&gt; origin/master  (forced update)
  </code></pre>
  
  <p>but <code>138b9ed</code> is just the latest commit in origin/master, and anyone might have committed after the force push; it is even possible that the force pusher himself did not commit anything, just rebased, so his name is not even present in the rewritten part of origin/master's history as an author.</p>
  
  <p>I also tried <code>git reflog origin/master</code>, but it just gives the same information: there is a record saying <code>git pull --prune (forced update)</code> with the commit id <code>138b9ed</code>, but that will again give the last committer into master, not the one who did the force push. Running <code>git reflog master</code> on the origin server would probably help, but GitHub does not give you that sort of access AFAIK.</p>
  
  <p>Is there any reliable way to find out whom the push originated from (and when)?</p>