A dozen years ago when Bob Sheheen was Democratic speaker of the S.C. House, he said something that has stuck with me -- some wisdom that some elected officials seem to forget:

"You don't have to be black to represent black people," he said. "And you don't have to be white to represent white people. I can be an effective advocate for black South Carolinians in my district, even though I'm white."

Now conservative members of the U.S. Supreme Court seem to have taken a page from Sheheen's book as they jumped into a fray over the shaping of legislative districts. In a June decision that likely will have a sweeping impact on future voting, the court said districts created to have a majority of black voters might not be the best idea for improving democracy. Instead, legislatures can use a host of factors to redraw districts, including creating districts to encourage biracial voting coalitions.

"Various studies suggest that the most effective way to maximize minority voting strength may be to create more influence or coalitional districts," Justice Sandra Day O'Connor wrote for the 5-4 majority. "Section 5 allows states to risk having fewer minority representatives in order to achieve greater overall representation of a minority group by increasing the number of representatives sympathetic to the interests of minority voters."

When South Carolina redrew state political lines for 1992, lawmakers sought to increase the number of so-called "black majority districts." While this tactic put more blacks in office -- including the positive result of leading to the election of the state's first black congressman (U.S. Rep. Jim Clyburn) in more than 100 years -- it had an additional effect: It made adjoining districts "whiter."

Following the creation of these black majority districts by an odd coalition of GOP and black Democratic lawmakers, a political realignment quickly ensued. In 1994, Republicans took over the S.C. House. A few years later, they took control of the state Senate.

Today, legislative districts are more heavily Democratic or heavily Republican than ever before. What's happened is the federal Voting Rights Act led to a kind of resegregation of the state via voting districts. By focusing on drawing districts to boost Democratic or Republican participation, lawmakers increased political polarization, which, in turn, diminished the power of the moderate voters.

"Because we are all herded into highly partisan districts, our elected representatives have no incentive to appeal to the moderate middle," said Atlanta Journal-Constitution writer Jay Bookman in a recent column.

By manipulating districts into black majority (heavily Democratic) and whiter (heavier GOP) districts, South Carolina also protected incumbents and created a dynamic for less political competition and participation.

In the 2002 elections, 50 Republican (all white) House members had no opposition. Some 38 Democrats (21 black; 17 white) had no opposition. Only 36 races were contested between parties. In effect, the results of the election largely were decided before voters got to the polls. Republicans only had to pick up 13 of 36 seats -- many of which leaned toward Republicans anyway -- to keep their majority in the House.

Notes Washington Post writer Thomas Edsall, "The GOP's goal has been to concentrate as many Democratic voters in as few districts as possible, increasing the likelihood of electing Republicans in surrounding districts. The strategy -- which helps elect black Democrats but defeat a larger number of white Democrats -- has contributed to the GOP takeover of several southern legislatures and congressional delegations in the past quarter-century."

With its new ruling, the Supreme Court is encouraging states such as South Carolina to dilute the "whiteness" of some districts to increase political competition. In South Carolina, this would tend to help Democrats, who are more successful in building biracial coalitions.

Legislators next are rescheduled to redraw lines in 2012. But because the state's lawmakers redrew this decade's lines for a second time this year, the courts could use the new Supreme Court opinion to issue more new maps -- if the just-passed reapportionment is challenged in court. And with this new ruling, it most likely will be.