diff --git a/metropolis/pkg/logtree/klog.go b/metropolis/pkg/logtree/klog.go
index 1c866f4..9d9b1ee 100644
--- a/metropolis/pkg/logtree/klog.go
+++ b/metropolis/pkg/logtree/klog.go
@@ -85,6 +85,7 @@
 		// We could instead emit that line as a raw log - however, this would lead to
 		// interleaving raw logging and leveled logging.
 		k.publisher.Errorf("Invalid klog line: %s", l.Data)
+		return
 	}
 	// TODO(q3k): should this be exposed as an API on LeveledLogger? How much should
 	// we permit library users to 'fake' logs? This would also permit us to get rid