public function expiresAfter($iGroupId)
    {
        if (empty($iGroupId)) {
            return null;
        }

        $oDb = Factory::service('Database');
        $oDb->select('password_rules');
        $oDb->where('id', $iGroupId);
        $oDb->limit(1);
        $oResult = $oDb->get(NAILS_DB_PREFIX . 'user_group');

        if ($oResult->num_rows() !== 1) {
            return null;
        }

        //  Decode the password rules
        $oGroupPwRules = json_decode($oResult->row()->password_rules);

        return empty($oGroupPwRules->expiresAfter) ? null : $oGroupPwRules->expiresAfter;
    }