diff --git a/testing/backend/unit/test_parse_json_fields_edge_cases.py b/testing/backend/unit/test_parse_json_fields_edge_cases.py
new file mode 100644
index 00000000..62b2fe51
--- /dev/null
+++ b/testing/backend/unit/test_parse_json_fields_edge_cases.py
@@ -0,0 +1,88 @@
+"""
+Additional unit tests for parse_json_fields edge cases in
+backend.secuscan.routes_json_helpers.
+
+These complement the existing 6 tests in test_routes_json_helpers.py which
+cover the happy path. These tests cover edge cases: empty field list,
+whitespace JSON, falsy parsed values, and empty rows list.
+"""
+
+import pytest
+from backend.secuscan.routes_json_helpers import parse_json_fields
+
+
+class TestParseJsonFieldsEdgeCases:
+    def test_empty_fields_list_returns_rows_unchanged(self):
+        rows = [{"name": "test", "value": "123"}]
+        result = parse_json_fields(rows, [])
+        assert result == rows
+        assert result[0]["name"] == "test"
+        assert result[0]["value"] == "123"
+
+    def test_whitespace_only_json_string_preserved(self):
+        rows = [{"field": "   "}]
+        result = parse_json_fields(rows, ["field"])
+        assert result[0]["field"] == "   "
+
+    def test_valid_json_array_parsed(self):
+        rows = [{"items": '["a", "b", "c"]'}]
+        result = parse_json_fields(rows, ["items"])
+        assert result[0]["items"] == ["a", "b", "c"]
+
+    def test_valid_json_number_parsed(self):
+        rows = [{"count": "42"}]
+        result = parse_json_fields(rows, ["count"])
+        assert result[0]["count"] == 42
+
+    def test_valid_json_boolean_true_parsed(self):
+        rows = [{"flag": "true"}]
+        result = parse_json_fields(rows, ["flag"])
+        assert result[0]["flag"] is True
+
+    def test_valid_json_boolean_false_parsed(self):
+        rows = [{"flag": "false"}]
+        result = parse_json_fields(rows, ["flag"])
+        assert result[0]["flag"] is False
+
+    def test_valid_json_null_parsed(self):
+        rows = [{"val": "null"}]
+        result = parse_json_fields(rows, ["val"])
+        assert result[0]["val"] is None
+
+    def test_valid_json_object_parsed(self):
+        rows = [{"meta": '{"source": "scan"}'}]
+        result = parse_json_fields(rows, ["meta"])
+        assert result[0]["meta"] == {"source": "scan"}
+
+    def test_falsy_integer_zero_preserved_after_parse(self):
+        rows = [{"count": "0"}]
+        result = parse_json_fields(rows, ["count"])
+        assert result[0]["count"] == 0
+
+    def test_falsy_boolean_false_preserved(self):
+        rows = [{"active": "false"}]
+        result = parse_json_fields(rows, ["active"])
+        assert result[0]["active"] is False
+
+    def test_mixed_rows_some_valid_json_some_not(self):
+        rows = [
+            {"field": '{"ok": true}'},
+            {"field": "not-json"},
+            {"field": "  invalid json  "},
+            {"other": "data"},
+        ]
+        result = parse_json_fields(rows, ["field"])
+        assert result[0]["field"] == {"ok": True}
+        assert result[1]["field"] == "not-json"
+        assert result[2]["field"] == "  invalid json  "
+        assert result[3] == {"other": "data"}
+
+    def test_empty_rows_list_returns_empty(self):
+        result = parse_json_fields([], ["field"])
+        assert result == []
+
+    def test_field_not_in_row_skipped(self):
+        rows = [{"name": "test", "other_field": '{"x":1}'}]
+        result = parse_json_fields(rows, ["missing_field", "other_field"])
+        assert result[0]["other_field"] == {"x": 1}
+        assert "missing_field" not in result[0]