Best Practice for Errors in RESTful API

Question

What are the best practices for returning HTTP status codes in RESTful API? I am using Laravel 4 for my PHP framework.

In the case of an error, should I use

Answer 1

There are some list of HTTP Status Code at Illuminate\Http\Response that extend to Symfony\Component\HttpFoundation\Response. You can use that in your class.

For example:

use Illuminate\Http\Response as LaravelResponse;
...
return Response::json('User Exists', LaravelResponse::HTTP_CONFLICT);

It much more readable.