diff --git a/pmd-apex/src/main/java/net/sourceforge/pmd/lang/apex/rule/security/ApexCRUDViolationRule.java b/pmd-apex/src/main/java/net/sourceforge/pmd/lang/apex/rule/security/ApexCRUDViolationRule.java
index dc8e8ee04a..d4185600a6 100644
--- a/pmd-apex/src/main/java/net/sourceforge/pmd/lang/apex/rule/security/ApexCRUDViolationRule.java
+++ b/pmd-apex/src/main/java/net/sourceforge/pmd/lang/apex/rule/security/ApexCRUDViolationRule.java
@@ -100,6 +100,8 @@ public class ApexCRUDViolationRule extends AbstractApexRule {
 
     @Override
     public void start(RuleContext ctx) {
+        // At the start of each rule execution, these member variables need to be fresh. So they're initialized in the
+        // .start() method instead of the constructor, since .start() is called before every execution.
         varToTypeMapping = new HashMap<>();
         typeToDMLOperationMapping = ArrayListMultimap.create();
         checkedTypeToDMLOperationViaESAPI = new HashMap<>();