How to check with the Rules module if a user has a custom picture?
Here's what I did, using a quick custom module to define and evaluate the condition that a user has uploaded a custom image to the core-provided Picture in the user account.

Module name: mymodule

This goes in mymodule.rules.inc:

/**
 * Implements hook_rules_condition_info()
 */
function mymodule_rules_condition_info() {
  return array(
    'mymodule_condition_user_has_picture' =&gt; array(
      'label' =&gt; t('User has picture'),
      'parameter' =&gt; array(
        'account' =&gt; array(
          'type' =&gt; 'user',
          'label' =&gt; t('User account')
        ),
      ),
      'group' =&gt; 'User',
    ),
  );
}

/**
 * Evaluates condition user_has_picture
 */
function mymodule_condition_user_has_picture($account) {
  if ($account-&gt;picture == NULL) {
    return false;
  } else {
    return true;
  }
}


Note that I've chosen to make the condition positive (returns TRUE if picture is found). If you want the condition to return true when the picture is NOT found, use the Negate option found in Rules.