This will work, but there's a lot of repetition going on with checking is current_user is an admin. So I'd write it like this:

    <li><%= link_to 'Courts or Tribunals', admin_courts_path %></li>
    <% if current_user.admin %>
      <li><%= link_to 'Address Types', admin_address_types_path %></li>
      <li><%= link_to 'Countries', admin_countries_path %></li>
      <li><%= link_to 'Counties', admin_counties_path %></li>
      <li><%= link_to 'Towns', admin_towns_path %></li>
      <li><%= link_to 'Court Types', admin_court_types_path %></li>
      <li><%= link_to 'Areas of law', admin_areas_of_law_path %></li>
      <li><%= link_to 'Opening Types', admin_opening_types_path %></li>
      <li><%= link_to 'Contact Types', admin_contact_types_path %></li>
      <li><%= link_to 'Facilities', admin_facilities_path %></li>
      <li><%= link_to 'Regions', admin_regions_path %></li>
      <li><%= link_to 'Areas', admin_areas_path %></li>
      <li><%= link_to 'Users', admin_users_path %></li>
    <% end %>