diff --git a/litellm/proxy/guardrails/guardrail_hooks/bedrock_guardrails.py b/litellm/proxy/guardrails/guardrail_hooks/bedrock_guardrails.py
index 8ef188bb23c..02d87a4962d 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/bedrock_guardrails.py
+++ b/litellm/proxy/guardrails/guardrail_hooks/bedrock_guardrails.py
@@ -82,7 +82,12 @@ def _redact_pii_matches(response_json: dict) -> dict:
         redacted_response = copy.deepcopy(response_json)
 
         # Get assessments from the response
-        assessments = redacted_response.get("assessments", [])
+        # NOTE: We use `.get("key") or []` instead of `.get("key", [])` because
+        # the Bedrock API can return explicit `null` for list fields (e.g. "regexes": null).
+        # In Python, dict.get("key", []) returns None (not []) when the key exists
+        # with a None/null value. The `or []` ensures we always get an iterable,
+        # preventing "TypeError: 'NoneType' object is not iterable".
+        assessments = redacted_response.get("assessments") or []
         if not assessments:
             return redacted_response
 
@@ -90,13 +95,13 @@ def _redact_pii_matches(response_json: dict) -> dict:
             # Redact PII entities in sensitive information policy
             sensitive_info_policy = assessment.get("sensitiveInformationPolicy")
             if sensitive_info_policy:
-                pii_entities = sensitive_info_policy.get("piiEntities", [])
+                pii_entities = sensitive_info_policy.get("piiEntities") or []
                 for pii_entity in pii_entities:
                     if "match" in pii_entity:
                         pii_entity["match"] = "[REDACTED]"
 
                 # Redact regex matches
-                regexes = sensitive_info_policy.get("regexes", [])
+                regexes = sensitive_info_policy.get("regexes") or []
                 for regex_match in regexes:
                     if "match" in regex_match:
                         regex_match["match"] = "[REDACTED]"
@@ -104,12 +109,12 @@ def _redact_pii_matches(response_json: dict) -> dict:
             # Redact custom word matches in word policy
             word_policy = assessment.get("wordPolicy")
             if word_policy:
-                custom_words = word_policy.get("customWords", [])
+                custom_words = word_policy.get("customWords") or []
                 for custom_word in custom_words:
                     if "match" in custom_word:
                         custom_word["match"] = "[REDACTED]"
 
-                managed_words = word_policy.get("managedWordLists", [])
+                managed_words = word_policy.get("managedWordLists") or []
                 for managed_word in managed_words:
                     if "match" in managed_word:
                         managed_word["match"] = "[REDACTED]"
@@ -682,7 +687,9 @@ class BedrockGuardrail(CustomGuardrail, BaseAWSLLM):
             return False
 
         # Check assessments to determine if any actions were BLOCKED (vs ANONYMIZED)
-        assessments = response.get("assessments", [])
+        # NOTE: Use `or []` instead of default param to handle explicit null from Bedrock API.
+        # See _redact_pii_matches() for detailed explanation of the null safety pattern.
+        assessments = response.get("assessments") or []
         if not assessments:
             return False
 
@@ -690,7 +697,7 @@ class BedrockGuardrail(CustomGuardrail, BaseAWSLLM):
             # Check topic policy
             topic_policy = assessment.get("topicPolicy")
             if topic_policy:
-                topics = topic_policy.get("topics", [])
+                topics = topic_policy.get("topics") or []
                 for topic in topics:
                     if topic.get("action") == "BLOCKED":
                         return True
@@ -698,7 +705,7 @@ class BedrockGuardrail(CustomGuardrail, BaseAWSLLM):
             # Check content policy
             content_policy = assessment.get("contentPolicy")
             if content_policy:
-                filters = content_policy.get("filters", [])
+                filters = content_policy.get("filters") or []
                 for filter_item in filters:
                     if filter_item.get("action") == "BLOCKED":
                         return True
@@ -706,11 +713,11 @@ class BedrockGuardrail(CustomGuardrail, BaseAWSLLM):
             # Check word policy
             word_policy = assessment.get("wordPolicy")
             if word_policy:
-                custom_words = word_policy.get("customWords", [])
+                custom_words = word_policy.get("customWords") or []
                 for custom_word in custom_words:
                     if custom_word.get("action") == "BLOCKED":
                         return True
-                managed_words = word_policy.get("managedWordLists", [])
+                managed_words = word_policy.get("managedWordLists") or []
                 for managed_word in managed_words:
                     if managed_word.get("action") == "BLOCKED":
                         return True
@@ -718,12 +725,12 @@ class BedrockGuardrail(CustomGuardrail, BaseAWSLLM):
             # Check sensitive information policy
             sensitive_info_policy = assessment.get("sensitiveInformationPolicy")
             if sensitive_info_policy:
-                pii_entities = sensitive_info_policy.get("piiEntities", [])
+                pii_entities = sensitive_info_policy.get("piiEntities") or []
                 if pii_entities:
                     for pii_entity in pii_entities:
                         if pii_entity.get("action") == "BLOCKED":
                             return True
-                regexes = sensitive_info_policy.get("regexes", [])
+                regexes = sensitive_info_policy.get("regexes") or []
                 if regexes:
                     for regex in regexes:
                         if regex.get("action") == "BLOCKED":
@@ -732,7 +739,7 @@ class BedrockGuardrail(CustomGuardrail, BaseAWSLLM):
             # Check contextual grounding policy
             contextual_grounding_policy = assessment.get("contextualGroundingPolicy")
             if contextual_grounding_policy:
-                grounding_filters = contextual_grounding_policy.get("filters", [])
+                grounding_filters = contextual_grounding_policy.get("filters") or []
                 for grounding_filter in grounding_filters:
                     if grounding_filter.get("action") == "BLOCKED":
                         return True
@@ -1391,7 +1398,9 @@ class BedrockGuardrail(CustomGuardrail, BaseAWSLLM):
         Raises:
             Exception: If content is blocked by Bedrock guardrail
         """
-        texts = inputs.get("texts", [])
+        # NOTE: Use `or []` to handle case where inputs["texts"] is explicitly None.
+        # dict.get("texts", []) would return None if the key exists with a None value.
+        texts = inputs.get("texts") or []
         try:
             verbose_proxy_logger.debug(
                 f"Bedrock Guardrail: Applying guardrail to {len(texts)} text(s)"