The State of South Carolina is at loggerheads with the federal Department of Justice over a matter that has perceived racial implications. At the heart of this issue is a problem that master data management practitioners know only too well.

Things came to a head a few weeks ago when the DOJ blocked a new South Carolina law, which would mandate that voters show photo identification cards to vote in state elections. Photo IDs would reduce voting fraud through impersonation, state officials said. The Justice Department sees the requirement differently--as a back-door way to suppress minority votes.

You can read the details here. The crux of the disagreement lies in the reliability (or rather, lack of reliability) of classifying voters based on demographic and related characteristics. South Carolina provided data that included 240,000 registered voters that it said didn't have the required identification based on numbers received from the state Department of Motor Vehicles. The DMV, however, questioned the numbers, saying the real number was probably closer to 80,000, once people who had died or moved away were accounted for. Now that’s a big difference. The DOJ went on to assert that the state failed to include several categories of existing registered voters, such as “inactive” voters who hadn't participated in several recent elections.

This is a classic master data management problem.

The solution is conceptually simple. Make an list of all persons living in or living outside but eligible to vote in South Carolina, attach a few key attributes such as current address, date moved into that address, past address, date moved into past address, Social Security number, driving license number, date of birth, date of death (if applicable), minority status, and last date voted … and voila, you can easily identify (a) total voters, (b) total minority voters, (c) statistics on active vs. inactive voters by minority status, (d) persons who voted in the last election but are now ineligible to vote because they died or moved away, and much more.

[ For more on master data management, see Master Data Management Comes Of Age. ]

In theory, there are a number of solidly reliable sources where we can get these details: the U.S. Postal Service, the Social Security Administration, state motor vehicles agencies, state and federal election departments and commissions. Surely these organizations have up-to-date and reliable data.

Don’t count on it!