diff --git a/elections/templates/elections/upload_voters.html b/elections/templates/elections/upload_voters.html
index c0ccdad..2b27ab8 100644
--- a/elections/templates/elections/upload_voters.html
+++ b/elections/templates/elections/upload_voters.html
@@ -4,7 +4,8 @@
 
 {% block extra_head %}
 <script>
-  $(document).ready(function($) {
+  {% if not election.sent_mail %}
+  document.addEventListener('DOMContentLoaded', () => {
     const fileInput = document.querySelector('#import-voters input[type=file]');
     fileInput.onchange = () => {
       if (fileInput.files.length > 0) {
@@ -13,6 +14,7 @@
       }
     };
   });
+  {% endif %}
 
 </script>
 {% endblock %}