In one of Google’s sample apps for Android Architecture Components they wrap the LiveData emitted object in a class that can contain a status, data, and message for the emitted object.
https://github.com/googlesamples/android-architecture-components/blob/master/GithubBrowserSample/app/src/main/java/com/android/example/github/vo/Resource.kt
With this approach you can use the status to determine if there was an error.