diff --git a/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores.ts b/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores.ts
index 7af9d66..a966186 100644
--- a/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores.ts
+++ b/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores.ts
@@ -95,9 +95,11 @@
     numberValue?: number
   ): string {
     const detailedInfo = labels[labelName] as DetailedLabelInfo;
-    for (const labelValue of Object.keys(detailedInfo.values)) {
-      if (Number(labelValue) === numberValue) {
-        return labelValue;
+    if (detailedInfo.values) {
+      for (const labelValue of Object.keys(detailedInfo.values)) {
+        if (Number(labelValue) === numberValue) {
+          return labelValue;
+        }
       }
     }
     const stringVal = `${numberValue}`;
diff --git a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.ts b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.ts
index 70f68ae..60a07a4 100644
--- a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.ts
+++ b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.ts
@@ -223,7 +223,7 @@
     if (
       !labelInfo ||
       !isDetailedLabelInfo(labelInfo) ||
-      !labelInfo.values[score]
+      !labelInfo.values?.[score]
     ) {
       return '';
     }
diff --git a/polygerrit-ui/app/types/common.ts b/polygerrit-ui/app/types/common.ts
index 5f196b1..8f5518a 100644
--- a/polygerrit-ui/app/types/common.ts
+++ b/polygerrit-ui/app/types/common.ts
@@ -198,7 +198,7 @@
   // This is not set when the change has no reviewers.
   all?: ApprovalInfo[];
   // Docs claim that 'values' is optional, but it is actually always set.
-  values: LabelValueToDescriptionMap; // A map of all values that are allowed for this label
+  values?: LabelValueToDescriptionMap; // A map of all values that are allowed for this label
   default_value?: number;
 }
 
diff --git a/polygerrit-ui/app/utils/label-util.ts b/polygerrit-ui/app/utils/label-util.ts
index fc83d77..60ac4d8 100644
--- a/polygerrit-ui/app/utils/label-util.ts
+++ b/polygerrit-ui/app/utils/label-util.ts
@@ -27,7 +27,7 @@
 export const CODE_REVIEW = 'Code-Review';
 
 export function getVotingRange(label?: LabelInfo): VotingRangeInfo | undefined {
-  if (!label || !isDetailedLabelInfo(label)) return undefined;
+  if (!label || !isDetailedLabelInfo(label) || !label.values) return undefined;
   const values = Object.keys(label.values).map(v => Number(v));
   values.sort((a, b) => a - b);
   if (!values.length) return undefined;