@s01us this looks wrong. I think it should be:

```ruby
if Discussion.find_by_id(params[:id])
  raise ActiveRecord::RecordNotFound
else
  render 'application/display_error', locals: { message: t('error.not_found') }
end
```

But the main thing that is concerning me is that we don't have any tests to make sure this code is behaving correctly. Also, the code I've written looks a bit confusing. Let's wait till @robguthrie gets here and see if he has any better ideas of how implement this and test it nicely/quickly.