When I try to import the data file into the database using the importer.php class Jamie created, I get an error:
Fatal error: Uncaught exception 'PDOException' with message
'SQLSTATE[42S22]: Column not found: 1054 Unknown column 'xml_id' in
'field list'' in
/home3/14/lang02/www/bailey_v2/includes/classes/Zend/Db/Statement/Pdo.php:228

The table 'criminals' in the database (and thus the derived Zend_Db_Table object 'criminals') has these five fields:
criminal_id
surname
given_name
gender_id_fk
age
The importCriminal method in the real file and the testImportXml method in my test file create a variable $new which has 5 fields in it:
surname
given_name
gender_id_fk
age
xml_id

When that array is inserted as a new record in the 'criminals' table, an error is generated. My guess is that's because the criminal_id field is automatically populated so we're trying to put 5 fields of data into a table with 4 fields. There is no field in the table for the "xml_id" value in the array.

The new data file validates, and if I import one of the existing data files I get the same error, so I don't think the data is the problem.
If I comment out the insert statement, no errors in my test method.
If I get rid of the xml_id field in the $new array, no errors in my test method.

Given that the value for the xml_id field is always null (as far as I can figure out as the element 'criminal' in the data has no attributes and specifically not an id attribute), I don't understand why it's being included in the insert at all. I'm guessing that the xml_id is used internally for the duration of processing only. It looks like its intended to be used in the method that resolves duplicate criminals.

public function importXml($file) {
$contents = file_get_contents($file);
$xml = new SimpleXMLElement($contents);
foreach ($xml->trial_file as $i => $trialFile) {
$criminalId = $this->_importCriminal($trialFile->criminal);
.
.
.
}

.
.
.
return true;
}

protected function _importCriminal($data) {
if (isset($data->attributes()->id)) {
$xmlId = $data->attributes()->id;
} else {
$xmlId = null;
}

$new = array(
'surname' => $data->surname,
'given_name' => $data->given_names,
'age' => $data->age,
'gender_id_fk' => array_search(strtolower($data->gender), $this->genderMap),
'xml_id' => $xmlId
);

$id = $this->tables['criminals']->insert($new); /* error thrown here */

$this->_importCriminalAliases($data->aliases->alias, $id);

return $id;
}