diff --git a/.github/workflows/python.yaml b/.github/workflows/python.yaml
index 08aa7962..fc12a3d1 100644
--- a/.github/workflows/python.yaml
+++ b/.github/workflows/python.yaml
@@ -25,32 +25,28 @@ jobs:
           libxml2-utils
         python -m pip install --upgrade pip
         pip install pytest
-        which xmllint
-        xmllint --version
         which pytest
 
     - name: Test with pytest
       run: |
         export PYTHONPATH=$(pwd)/scripts:$(pwd)/scripts/parse_tools
+        which xmllint
+        xmllint --version
         pytest -v test/
 
-  doctest:
-    runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        python-version: ['3.8', '3.9', '3.10', '3.11', '3.12']
-
-    steps:
-    - uses: actions/checkout@v3
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
-      with:
-        python-version: ${{ matrix.python-version }}
-    - name: Install dependencies
+    - name: Test with pytest using bad xmllint (xmllint wrapper)
       run: |
-        python -m pip install --upgrade pip
-        pip install pytest
-    - name: Doctest
+        export XMLLINT_REAL=$(which xmllint)
+        export PYTHONPATH=$(pwd)/scripts:$(pwd)/scripts/parse_tools
+        export PATH=$(pwd)/test/unit_tests/xmllint_wrapper:${PATH}
+        export | grep PATH
+        which xmllint
+        xmllint --version
+        pytest -v test/
+
+    - name: Test with doctest
       run: |
         export PYTHONPATH=$(pwd)/scripts:$(pwd)/scripts/parse_tools
+        which xmllint
+        xmllint --version
         pytest -v scripts/ --doctest-modules
diff --git a/scripts/parse_tools/xml_tools.py b/scripts/parse_tools/xml_tools.py
index ed50dd43..dfeb9e7a 100644
--- a/scripts/parse_tools/xml_tools.py
+++ b/scripts/parse_tools/xml_tools.py
@@ -20,7 +20,6 @@
 
 # Global data
 _INDENT_STR = "  "
-_XMLLINT = shutil.which('xmllint') # Blank if not installed
 beg_tag_re = re.compile(r"([<][^/][^<>]*[^/][>])")
 end_tag_re = re.compile(r"([<][/][^<>/]+[>])")
 simple_tag_re = re.compile(r"([<][^/][^<>/]+[/][>])")
@@ -37,67 +36,6 @@ def __init__(self, message):
         """Initialize this exception"""
         super().__init__(message)
 
-###############################################################################
-def call_command(commands, logger, silent=False):
-###############################################################################
-    """
-    Try a command line and return the output on success (None on failure)
-    >>> _LOGGER = init_log('xml_tools')
-    >>> set_log_to_null(_LOGGER)
-    >>> call_command(['ls', 'really__improbable_fffilename.foo'], _LOGGER) #doctest: +IGNORE_EXCEPTION_DETAIL
-    Traceback (most recent call last):
-    CCPPError: Execution of 'ls really__improbable_fffilename.foo' failed:
-    [Errno 2] No such file or directory
-    >>> call_command(['ls', 'really__improbable_fffilename.foo'], _LOGGER, silent=True)
-    False
-    >>> call_command(['ls'], _LOGGER)
-    True
-    >>> try:
-    ...    call_command(['ls','--invalid-option'], _LOGGER)
-    ... except CCPPError as e:
-    ...    print(str(e))
-    Execution of 'ls --invalid-option' failed with code: 2
-    Error output: ls: unrecognized option '--invalid-option'
-    Try 'ls --help' for more information.
-    >>> try:
-    ...    os.chdir(os.path.dirname(__file__))
-    ...    call_command(['ls', os.path.basename(__file__), 'foo.bar.baz'], _LOGGER)
-    ... except CCPPError as e:
-    ...    print(str(e))
-    Execution of 'ls xml_tools.py foo.bar.baz' failed with code: 2
-    xml_tools.py
-    Error output: ls: cannot access 'foo.bar.baz': No such file or directory
-    """
-    result = False
-    outstr = ''
-    try:
-        cproc = subprocess.run(commands, check=True,
-                                capture_output=True)
-        if not silent:
-            logger.debug(cproc.stdout)
-        # end if
-        result = cproc.returncode == 0
-    except (OSError, CCPPError, subprocess.CalledProcessError) as err:
-        if silent:
-            result = False
-        else:
-            cmd = ' '.join(commands)
-            outstr = f"Execution of '{cmd}' failed with code: {err.returncode}\n"
-            outstr += f"{err.output.decode('utf-8', errors='replace').strip()}"
-            if hasattr(err, 'stderr') and err.stderr:
-                stderr_str = err.stderr.decode('utf-8', errors='replace').strip()
-                if stderr_str:
-                    if err.output:
-                        outstr += os.linesep
-                    # end if
-                    outstr += f"Error output: {stderr_str}"
-                # end if
-            # end if
-            raise CCPPError(outstr) from err
-        # end if
-    # end of try
-    return result
-
 ###############################################################################
 def find_schema_version(root):
 ###############################################################################
@@ -173,8 +111,7 @@ def find_schema_file(schema_root, version, schema_path=None):
     return None
 
 ###############################################################################
-def validate_xml_file(filename, schema_root, version, logger,
-                      schema_path=None, error_on_noxmllint=False):
+def validate_xml_file(filename, schema_root, version, logger, schema_path=None):
 ###############################################################################
     """
     Find the appropriate schema and validate the XML file, <filename>,
@@ -209,19 +146,39 @@ def validate_xml_file(filename, schema_root, version, logger,
         emsg = "validate_xml_file: Cannot open schema, '{}'"
         raise CCPPError(emsg.format(schema_file))
     # end if
-    if _XMLLINT:
-        logger.debug("Checking file {} against schema {}".format(filename,
-                                                                 schema_file))
-        cmd = [_XMLLINT, '--noout', '--schema', schema_file, filename]
-        result = call_command(cmd, logger)
-        return result
+    
+    # Find xmllint
+    xmllint = shutil.which('xmllint') # Blank if not installed
+    if not xmllint:
+        msg = "xmllint not found, could not validate file {}"
+        raise CCPPError("validate_xml_file: " + msg.format(filename))
     # end if
-    lmsg = "xmllint not found, could not validate file {}"
-    if error_on_noxmllint:
-        raise CCPPError("validate_xml_file: " + lmsg.format(filename))
+
+    # Validate XML file against schema
+    logger.debug("Checking file {} against schema {}".format(filename,
+                                                             schema_file))
+    cmd = [xmllint, '--noout', '--schema', schema_file, filename]    
+    cproc = subprocess.run(cmd, check=False, capture_output=True)
+    if cproc.returncode == 0:
+        # We got a pass return code but some versions of xmllint do not
+        # correctly return an error code on non-validation so double check
+        # the result
+        result = b'validates' in cproc.stdout or b'validates' in cproc.stderr
+    else:
+        result = False
     # end if
-    logger.warning(lmsg.format(filename))
-    return True # We could not check but still need to proceed
+    if result:
+        logger.debug(cproc.stdout)
+        logger.debug(cproc.stderr)
+        return result
+    else:
+        cmd = ' '.join(cmd)
+        outstr = f"Execution of '{cmd}' failed with code: {cproc.returncode}\n"
+        if cproc.stdout:
+            outstr += f"{cproc.stdout.decode('utf-8', errors='replace').strip()}\n"
+        if cproc.stderr:
+            outstr += f"{cproc.stderr.decode('utf-8', errors='replace').strip()}\n"
+        raise CCPPError(outstr)
 
 ###############################################################################
 def read_xml_file(filename, logger=None):
@@ -281,6 +238,7 @@ def load_suite_by_name(suite_name, group_name, file, logger=None):
         >>> import tempfile
         >>> import xml.etree.ElementTree as ET
         >>> logger = init_log('xml_tools')
+        >>> set_log_to_null(logger)
         >>> # Create temporary files for the nested suites
         >>> tmpdir = tempfile.TemporaryDirectory()
         >>> file1_path = os.path.join(tmpdir.name, "file1.xml")
@@ -310,7 +268,7 @@ def load_suite_by_name(suite_name, group_name, file, logger=None):
     schema_version = find_schema_version(root)
     res = validate_xml_file(file, 'suite', schema_version, logger)
     if not res:
-        raise CCPPError(f"Invalid suite definition file, '{sdf}'")
+        raise CCPPError(f"Invalid suite definition file, '{file}'")
     suite = root
     if suite.attrib.get("name") == suite_name:
         if group_name:
@@ -348,6 +306,7 @@ def replace_nested_suite(element, nested_suite, default_path, logger):
         >>> import xml.etree.ElementTree as ET
         >>> from types import SimpleNamespace
         >>> logger = init_log('xml_tools')
+        >>> set_log_to_null(logger)
         >>> tmpdir = tempfile.TemporaryDirectory()
         >>> file1_path = os.path.join(tmpdir.name, "file1.xml")
         >>> with open(file1_path, "w") as f:
@@ -459,6 +418,7 @@ def expand_nested_suites(suite, default_path, logger=None):
         >>> import tempfile
         >>> import xml.etree.ElementTree as ET
         >>> logger = init_log('xml_tools')
+        >>> set_log_to_null(logger)
         >>> tmpdir = tempfile.TemporaryDirectory()
         >>> file1_path = os.path.join(tmpdir.name, "file1.xml")
         >>> file2_path = os.path.join(tmpdir.name, "file2.xml")
diff --git a/test/unit_tests/test_sdf.py b/test/unit_tests/test_sdf.py
index f06d189f..5dd73d95 100644
--- a/test/unit_tests/test_sdf.py
+++ b/test/unit_tests/test_sdf.py
@@ -194,8 +194,7 @@ def test_good_v1_sdf(self):
             schema_version = find_schema_version(xml_root)
             self.assertEqual(schema_version[0], 1)
             self.assertEqual(schema_version[1], 0)
-            res = validate_xml_file(source, 'suite', schema_version, logger,
-                                    error_on_noxmllint=True)
+            res = validate_xml_file(source, 'suite', schema_version, logger)
             self.assertTrue(res)
             write_xml_file(xml_root, compare, logger)
             amsg = f"{compare} does not exist"
@@ -226,8 +225,7 @@ def test_good_v2_sdf_01(self):
         self.assertEqual(schema_version[1], 0)
         expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
         write_xml_file(xml_root, compare, logger)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res)
         amsg = f"{compare} does not exist"
         self.assertTrue(os.path.exists(compare), msg=amsg)
@@ -257,8 +255,7 @@ def test_good_v2_sdf_02(self):
         self.assertEqual(schema_version[1], 0)
         expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
         write_xml_file(xml_root, compare, logger)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res)
         amsg = f"{compare} does not exist"
         self.assertTrue(os.path.exists(compare), msg=amsg)
@@ -289,8 +286,7 @@ def test_good_v2_sdf_03(self):
         self.assertEqual(schema_version[1], 0)
         expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
         write_xml_file(xml_root, compare, logger)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res)
         amsg = f"{compare} does not exist"
         self.assertTrue(os.path.exists(compare), msg=amsg)
@@ -321,8 +317,7 @@ def test_good_v2_sdf_04(self):
         self.assertEqual(schema_version[1], 0)
         expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
         write_xml_file(xml_root, compare, logger)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res)
         amsg = f"{compare} does not exist"
         self.assertTrue(os.path.exists(compare), msg=amsg)
@@ -349,8 +344,7 @@ def test_bad_v2_suite_tag_sdf(self):
         # logic handles the correct behavior (validation fails ==>
         # exit code /= 0 ==> CCPPError).
         try:
-            res = validate_xml_file(source, 'suite', schema_version, logger,
-                                    error_on_noxmllint=True)
+            res = validate_xml_file(source, 'suite', schema_version, logger)
         except Exception as e:
             emsg = "Schemas validity error : Element 'suite': This element is not expected."
             msg = str(e)
@@ -369,8 +363,7 @@ def test_bad_v2_suite_duplicate_group1(self):
         schema_version = find_schema_version(xml_root)
         self.assertEqual(schema_version[0], 2)
         self.assertEqual(schema_version[1], 0)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res, msg="Initial suite file should be valid")
         with self.assertRaises(Exception) as context:
             expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
@@ -397,8 +390,7 @@ def test_bad_v2_suite_missing_group(self):
         schema_version = find_schema_version(xml_root)
         self.assertEqual(schema_version[0], 2)
         self.assertEqual(schema_version[1], 0)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res, msg="Initial suite file should be valid")
         with self.assertRaises(Exception) as context:
             expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
@@ -424,8 +416,7 @@ def test_bad_v2_suite_missing_file(self):
         # See note about different behavior of xmllint versions
         # in test test_bad_v2_suite_tag_sdf above.
         try:
-            res = validate_xml_file(source, 'suite', schema_version, logger,
-                                    error_on_noxmllint=True)
+            res = validate_xml_file(source, 'suite', schema_version, logger)
         except Exception as e:
             emsg = "Schemas validity error : Element 'nested_suite': " + \
                 "The attribute 'file' is required but missing."
@@ -446,8 +437,7 @@ def test_bad_v2_suite_missing_loaded_suite(self):
         schema_version = find_schema_version(xml_root)
         self.assertEqual(schema_version[0], 2)
         self.assertEqual(schema_version[1], 0)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res, msg="Initial suite file should be valid")
         with self.assertRaises(Exception) as context:
             expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
@@ -471,8 +461,7 @@ def test_bad_v2_suite_infinite_group_recursion(self):
         schema_version = find_schema_version(xml_root)
         self.assertEqual(schema_version[0], 2)
         self.assertEqual(schema_version[1], 0)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res, msg="Initial suite file should be valid")
         with self.assertRaises(Exception) as context:
             expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
@@ -496,8 +485,7 @@ def test_bad_v2_suite_infinite_suite_recursion(self):
         schema_version = find_schema_version(xml_root)
         self.assertEqual(schema_version[0], 2)
         self.assertEqual(schema_version[1], 0)
-        res = validate_xml_file(source, 'suite', schema_version, logger,
-                                error_on_noxmllint=True)
+        res = validate_xml_file(source, 'suite', schema_version, logger)
         self.assertTrue(res, msg="Initial suite file should be valid")
         with self.assertRaises(Exception) as context:
             expand_nested_suites(xml_root, _SAMPLE_FILES_DIR, logger=logger)
diff --git a/test/unit_tests/xmllint_wrapper/xmllint b/test/unit_tests/xmllint_wrapper/xmllint
new file mode 100755
index 00000000..4f043c1c
--- /dev/null
+++ b/test/unit_tests/xmllint_wrapper/xmllint
@@ -0,0 +1,24 @@
+#!/usr/bin/env python3
+
+# This is a wrapper around xmllint to emulate the "bad behavior"
+# of some xmllint versions that return an exit code 0 even if the
+# validation fails. It requires the full path to the "real" xmllint
+# executable to be defined as environment variable XMLLINT_REAL
+
+import os
+import shutil
+import subprocess
+import sys
+
+xmllint = os.getenv("XMLLINT_REAL")
+if not xmllint:
+    raise Exception("xmllint not found")
+
+cmd = [xmllint] + sys.argv[1:]
+cproc = subprocess.run(cmd, check=False, capture_output=True)
+if cproc.stdout:
+    sys.stdout.write(cproc.stdout.decode('utf-8', errors='replace').strip()+"\n")
+if cproc.stderr:
+    sys.stderr.write(cproc.stderr.decode('utf-8', errors='replace').strip()+"\n")
+# Exit with an exit code of zero no matter what
+sys.exit(0)