Admin Post List Only Show One Category

I found a hacky solution involving redirecting the user:

if ((basename($_SERVER['SCRIPT_NAME']) == 'edit.php')) {
// your code here
$author = wp_get_current_user();
if(isset($author->roles[0])){ 
    $current_role = $author->roles[0];
}else{
    $current_role="no_role";
}

if($current_role == 'ai1ec_event_assistant' && ($_GET['post_type']==''&&$_GET['category_name']=='')){ 
    header("Location:/wp-admin/edit.php?category_name=events-list");    
}

}