diff --git a/litellm/proxy/decisions_endpoints/endpoints.py b/litellm/proxy/decisions_endpoints/endpoints.py
index 2b908a8a089..4170e3a13c3 100644
--- a/litellm/proxy/decisions_endpoints/endpoints.py
+++ b/litellm/proxy/decisions_endpoints/endpoints.py
@@ -40,6 +40,14 @@ async def _invalid_request(
     )
 
 
+async def _request_data(request: Request, user_api_key_dict: UserAPIKeyAuth) -> dict[str, object]:
+    body: Final = await request.body()
+    try:
+        return _REQUEST_DATA_ADAPTER.validate_json(body)
+    except ValidationError as error:
+        raise await _invalid_request(raw_data={}, error=error, user_api_key_dict=user_api_key_dict)
+
+
 async def _process_systemone(
     request: Request,
     fastapi_response: Response,
@@ -133,7 +141,7 @@ async def systemone(
         request=request,
         fastapi_response=fastapi_response,
         user_api_key_dict=user_api_key_dict,
-        raw_data=_REQUEST_DATA_ADAPTER.validate_json(await request.body()),
+        raw_data=await _request_data(request, user_api_key_dict),
         openai_body=None,
     )
 
@@ -155,7 +163,7 @@ async def decisions(
     fastapi_response: Response,
     user_api_key_dict: Annotated[UserAPIKeyAuth, Depends(user_api_key_auth)],
 ):
-    raw_data: Final = _REQUEST_DATA_ADAPTER.validate_json(await request.body())
+    raw_data: Final = await _request_data(request, user_api_key_dict)
     try:
         openai_body: Final = _OPENAI_DECISION_REQUEST_BODY_ADAPTER.validate_python(raw_data)
     except ValidationError as error:
diff --git a/tests/unit/proxy/decisions_endpoints/test_endpoints.py b/tests/unit/proxy/decisions_endpoints/test_endpoints.py
index 0650387d280..f61507e1d1d 100644
--- a/tests/unit/proxy/decisions_endpoints/test_endpoints.py
+++ b/tests/unit/proxy/decisions_endpoints/test_endpoints.py
@@ -421,6 +421,22 @@ def test_openai_format_decisions_rejects_bodies_it_cannot_translate(
     assert not upstream.called
 
 
+@pytest.mark.parametrize("endpoint", ("/v1/systemone", "/v1/decisions"))
+@pytest.mark.parametrize("raw_body", (b"", b"{not json"), ids=("empty", "malformed"))
+def test_a_body_that_is_not_json_is_a_client_error(
+    client: TestClient,
+    respx_mock: respx.MockRouter,
+    endpoint: str,
+    raw_body: bytes,
+) -> None:
+    upstream: Final = respx_mock.post("https://api.perplexity.ai/v1/decisions").respond(json=_RESPONSE)
+
+    response: Final = client.post(endpoint, content=raw_body, headers={"Content-Type": "application/json"})
+
+    assert response.status_code == 400, response.text
+    assert not upstream.called
+
+
 def _decisions_feature() -> LazyFeature:
     return next(feature for feature in LAZY_FEATURES if feature.name == "decisions")