From the job posting on glassdoor.com:

An extensive pre-employment background investigation will be conducted on all applicants who have been offered a position with Dallas County. The hiring process involves successful completion of each step. The steps include:

 - Criminal History Review,
 - Traffic Violations Record,
 - Review of Personal History Statement and Documents,
 - Physical Examination, and
 - Background Investigation.

Oops! They were just kidding about all that security stuff. Notice that the last line says it all:

    persons with a criminal background
    are encouraged to apply.

As always, if you know something, say something, and say it to WHISTLEBLOWER@openrecords.org.