Making illegal play during ko causes the client to disconnect

[beejunk]

Summary

During a ko battle, if a user attempts to reclaim the ko before playing elsewhere (i.e. playing in an illegal spot), then the client will throw an error and disconnect the user from the server.

Expected behavior

The user should not be allowed to make the play and the game should continue. Ideally, some sort of indication should be given that the play is illegal

[peterjoel]

It's still happening, 4 years later.

What's actually happening here? Is it an unexpected message from the server, causing an exception to be thrown but not caught?