diff --git a/src/py/flwr_tool/check_copyright.py b/src/py/flwr_tool/check_copyright.py
index 60dd7f2954ff..4ebcab823a38 100755
--- a/src/py/flwr_tool/check_copyright.py
+++ b/src/py/flwr_tool/check_copyright.py
@@ -35,6 +35,7 @@ def _get_file_creation_year(filepath: str):
         ["git", "log", "--diff-filter=A", "--format=%ai", "--", filepath],
         stdout=subprocess.PIPE,
         text=True,
+        check=True,
     )
     date_str = result.stdout.splitlines()[-1]  # Get the first commit date
     creation_year = date_str.split("-")[0]  # Extract the year
diff --git a/src/py/flwr_tool/fix_copyright.py b/src/py/flwr_tool/fix_copyright.py
index 378e0749f4ce..5366cd5ad82e 100755
--- a/src/py/flwr_tool/fix_copyright.py
+++ b/src/py/flwr_tool/fix_copyright.py
@@ -15,26 +15,33 @@
 from flwr_tool.init_py_check import get_init_dir_list_and_warnings
 
 
+def _insert_or_edit_copyright(py_file: Path) -> None:
+    contents = py_file.read_text()
+    lines = contents.splitlines()
+    creation_year = _get_file_creation_year(str(py_file.absolute()))
+    expected_copyright = COPYRIGHT_FORMAT.format(creation_year)
+
+    if expected_copyright not in contents:
+        if "Copyright" in lines[0]:
+            end_index = 0
+            for idx, line in enumerate(lines):
+                if (
+                    line.strip()
+                    == COPYRIGHT_FORMAT.rsplit("\n", maxsplit=1)[-1].strip()
+                ):
+                    end_index = idx + 1
+                    break
+            lines = lines[end_index:]
+
+        lines.insert(0, expected_copyright)
+    py_file.write_text("\n".join(lines))
+
+
 def _fix_copyright(dir_list: List[str]) -> None:
     for valid_dir in dir_list:
         dir_path = Path(valid_dir)
         for py_file in dir_path.glob("*.py"):
-            contents = py_file.read_text()
-            lines = contents.splitlines()
-            creation_year = _get_file_creation_year(str(py_file.absolute()))
-            expected_copyright = COPYRIGHT_FORMAT.format(creation_year)
-
-            if expected_copyright not in contents:
-                if "Copyright" in lines[0]:
-                    end_index = 0
-                    for i, line in enumerate(lines):
-                        if line.strip() == COPYRIGHT_FORMAT.split("\n")[-1].strip():
-                            end_index = i + 1
-                            break
-                    lines = lines[end_index:]
-
-                lines.insert(0, expected_copyright)
-            py_file.write_text("\n".join(lines))
+            _insert_or_edit_copyright(py_file)
 
 
 if __name__ == "__main__":