Apparently user with id from the form is not found with onlyTrashed
scope.
You should check the query (run DB::getQueryLog() for example) and data in your db, but first change the method to firstOrFail
:
$user = Emp::onlyTrashed()->where('id', '=', Input::get('actEmpId'))->firstOrFail();
It will throw ModelNotFoundException
if nothing was found, so you can catch it and do whatever is needed, thus avoid calling method on null error.