diff --git a/litellm/proxy/management_endpoints/internal_user_endpoints.py b/litellm/proxy/management_endpoints/internal_user_endpoints.py
index 65bc4ebdaf..b69969bdee 100644
--- a/litellm/proxy/management_endpoints/internal_user_endpoints.py
+++ b/litellm/proxy/management_endpoints/internal_user_endpoints.py
@@ -902,6 +902,42 @@ async def get_user_key_counts(
     return result
 
 
+def _validate_sort_params(
+    sort_by: Optional[str], sort_order: str
+) -> Optional[Dict[str, str]]:
+    order_by: Dict[str, str] = {}
+
+    if sort_by is None:
+        return None
+    # Validate sort_by is a valid column
+    valid_columns = [
+        "user_id",
+        "user_email",
+        "created_at",
+        "spend",
+        "user_alias",
+        "user_role",
+    ]
+    if sort_by not in valid_columns:
+        raise HTTPException(
+            status_code=400,
+            detail={
+                "error": f"Invalid sort column. Must be one of: {', '.join(valid_columns)}"
+            },
+        )
+
+    # Validate sort_order
+    if sort_order.lower() not in ["asc", "desc"]:
+        raise HTTPException(
+            status_code=400,
+            detail={"error": "Invalid sort order. Must be 'asc' or 'desc'"},
+        )
+
+    order_by[sort_by] = sort_order.lower()
+
+    return order_by
+
+
 @router.get(
     "/user/list",
     tags=["Internal User management"],
@@ -996,33 +1032,7 @@ async def get_users(
     where_conditions = {k: v for k, v in where_conditions.items() if v is not None}
 
     # Build order_by conditions
-    order_by: Dict[str, str] = {}
-    if sort_by:
-        # Validate sort_by is a valid column
-        valid_columns = [
-            "user_id",
-            "user_email",
-            "created_at",
-            "spend",
-            "user_alias",
-            "user_role",
-        ]
-        if sort_by not in valid_columns:
-            raise HTTPException(
-                status_code=400,
-                detail={
-                    "error": f"Invalid sort column. Must be one of: {', '.join(valid_columns)}"
-                },
-            )
-
-        # Validate sort_order
-        if sort_order.lower() not in ["asc", "desc"]:
-            raise HTTPException(
-                status_code=400,
-                detail={"error": "Invalid sort order. Must be 'asc' or 'desc'"},
-            )
-
-        order_by[sort_by] = sort_order.lower()
+    order_by: Optional[Dict[str, str]] = _validate_sort_params(sort_by, sort_order)
 
     users = await prisma_client.db.litellm_usertable.find_many(
         where=where_conditions,
diff --git a/tests/litellm/proxy/management_endpoints/test_internal_user_endpoints.py b/tests/litellm/proxy/management_endpoints/test_internal_user_endpoints.py
index deef94c15a..360f21f171 100644
--- a/tests/litellm/proxy/management_endpoints/test_internal_user_endpoints.py
+++ b/tests/litellm/proxy/management_endpoints/test_internal_user_endpoints.py
@@ -153,3 +153,19 @@ async def test_get_users_includes_timestamps(mocker):
     assert user_response.created_at == mock_user_data["created_at"]
     assert user_response.updated_at == mock_user_data["updated_at"]
     assert user_response.key_count == 0
+
+
+def test_validate_sort_params():
+    """
+    Test that validate_sort_params returns None if sort_by is None
+    """
+    from litellm.proxy.management_endpoints.internal_user_endpoints import (
+        _validate_sort_params,
+    )
+
+    assert _validate_sort_params(None, "asc") is None
+    assert _validate_sort_params(None, "desc") is None
+    assert _validate_sort_params("user_id", "asc") == {"user_id": "asc"}
+    assert _validate_sort_params("user_id", "desc") == {"user_id": "desc"}
+    with pytest.raises(Exception):
+        _validate_sort_params("user_id", "invalid")