diff --git a/godoc/static/playground.js b/godoc/static/playground.js
index aad459fa..1b7be65a 100644
--- a/godoc/static/playground.js
+++ b/godoc/static/playground.js
@@ -109,7 +109,10 @@ function HTTPTransport(enableVet) {
 						dataType: "json",
 						success: function(dataVet) {
 							if (dataVet.Errors) {
-								// inject errors from the vet as the first event in the output
+								if (!data.Events) {
+									data.Events = [];
+								}
+								// inject errors from the vet as the first events in the output
 								data.Events.unshift({Message: 'Go vet exited.\n\n', Kind: 'system', Delay: 0});
 								data.Events.unshift({Message: dataVet.Errors, Kind: 'stderr', Delay: 0});
 							}
diff --git a/godoc/static/static.go b/godoc/static/static.go
index 05117621..20edbe6c 100644
--- a/godoc/static/static.go
+++ b/godoc/static/static.go
@@ -2398,7 +2398,10 @@ function HTTPTransport(enableVet) {
 						dataType: "json",
 						success: function(dataVet) {
 							if (dataVet.Errors) {
-								// inject errors from the vet as the first event in the output
+								if (!data.Events) {
+									data.Events = [];
+								}
+								// inject errors from the vet as the first events in the output
 								data.Events.unshift({Message: 'Go vet exited.\n\n', Kind: 'system', Delay: 0});
 								data.Events.unshift({Message: dataVet.Errors, Kind: 'stderr', Delay: 0});
 							}