Handle user abuse

[eluser]olof84[/eluser]
How should I handle forbidden user actions in a CI project?

For example:

Code:

try {
     if($action == 'forbidden')
     {
          throw new exception('Forbidden action!');
     }
} catch (Exception $e)
{
      show_error ($e->getMessage(), 500);
}

The example above will call the general_error.php site which has an static header text (in my case: 'Sorry an error happened'). This dose not seem like the best way to handle user abuse.

Further more the example above will not log the user abuse.