diff --git a/solr/core/src/java/org/apache/solr/cloud/OverseerCollectionProcessor.java b/solr/core/src/java/org/apache/solr/cloud/OverseerCollectionProcessor.java
index 57c7d26a093..7507cf93290 100644
--- a/solr/core/src/java/org/apache/solr/cloud/OverseerCollectionProcessor.java
+++ b/solr/core/src/java/org/apache/solr/cloud/OverseerCollectionProcessor.java
@@ -69,6 +69,7 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
 
@@ -352,7 +353,7 @@ public class OverseerCollectionProcessor implements Runnable, ClosableThread {
         deleteReplica(zkStateReader.getClusterState(), message, results);
       } else if (MIGRATE.equals(operation)) {
         migrate(zkStateReader.getClusterState(), message, results);
-      } else if(REMOVEROLE.toString().toLowerCase().equals(operation) || ADDROLE.toString().toLowerCase().equals(operation) ){
+      } else if(REMOVEROLE.toString().toLowerCase(Locale.ROOT).equals(operation) || ADDROLE.toString().toLowerCase(Locale.ROOT).equals(operation) ){
         processRoleCommand(message, operation);
       }
 
@@ -388,10 +389,10 @@ public class OverseerCollectionProcessor implements Runnable, ClosableThread {
 
     List nodeList= (List) roles.get(roleName);
     if(nodeList == null) roles.put(roleName, nodeList = new ArrayList());
-    if(ADDROLE.toString().toLowerCase().equals(operation) ){
+    if(ADDROLE.toString().toLowerCase(Locale.ROOT).equals(operation) ){
       log.info("Overseer role added to {}", node);
       if(!nodeList.contains(node)) nodeList.add(node);
-    } else if(REMOVEROLE.toString().toLowerCase().equals(operation)) {
+    } else if(REMOVEROLE.toString().toLowerCase(Locale.ROOT).equals(operation)) {
       log.info("Overseer role removed from {}", node);
       nodeList.remove(node);
     }
diff --git a/solr/core/src/java/org/apache/solr/handler/admin/CollectionsHandler.java b/solr/core/src/java/org/apache/solr/handler/admin/CollectionsHandler.java
index 0fd39f01e7f..94c4d5f1e7e 100644
--- a/solr/core/src/java/org/apache/solr/handler/admin/CollectionsHandler.java
+++ b/solr/core/src/java/org/apache/solr/handler/admin/CollectionsHandler.java
@@ -53,6 +53,7 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Iterator;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
 
@@ -198,11 +199,11 @@ public class CollectionsHandler extends RequestHandlerBase {
 
   private void handleRole(CollectionAction action, SolrQueryRequest req, SolrQueryResponse rsp) throws KeeperException, InterruptedException {
     req.getParams().required().check("role", "node");
-    Map<String, Object> map = ZkNodeProps.makeMap(Overseer.QUEUE_OPERATION, action.toString().toLowerCase());
+    Map<String, Object> map = ZkNodeProps.makeMap(Overseer.QUEUE_OPERATION, action.toString().toLowerCase(Locale.ROOT));
     copyIfNotNull(req.getParams(), map,"role", "node");
     ZkNodeProps m = new ZkNodeProps(map);
     if(!KNOWN_ROLES.contains(m.getStr("role"))) throw new SolrException(ErrorCode.BAD_REQUEST,"Unknown role. Supported roles are ,"+ KNOWN_ROLES);
-    handleResponse(action.toString().toLowerCase(), m, rsp);
+    handleResponse(action.toString().toLowerCase(Locale.ROOT), m, rsp);
   }
 
   public static long DEFAULT_ZK_TIMEOUT = 60*1000;