Shelby County is booming. The Birmingham suburb is lined with strip malls, subdivisions, and small factories, in what was once sleepy farmland. The population has grown fivefold since 1970 to about 200,000. Change in this bedroom community is afoot, at least on the surface.

But the federal government thinks an underlying threat of discrimination remains throughout Alabama and other parts of the country in perhaps the most hard-fought franchise in the Constitution: The right to vote.

Competing voices in this county, echoes of decades-long debates over equal access to the polls, now spill out in a 21st century fight, one that has reached the U.S. Supreme Court.

"I think they are looking at this situation through rose-colored glasses," says the Rev. Dr. Harry Jones, a local civil rights leader, about the current majority white power structure in Shelby. "I think they have painted a picture to make the outside world believe that racism is no more, but if you dig beneath the surface I think you'll find what you are looking for."

But a longtime county leader says things truly have changed for the better.

"Here, now, in this decade, we have black registered voters at a percentage that is equal, and at some occasions exceeding, the voting of the white population," says county attorney Frank "Butch" Ellis, Jr. "It's hard to find that there's any discrimination here, and certainly there's nothing in the congressional record."

Major case for court this term

Now the nine-member high court is poised to decide whether the key enforcement provision of the landmark Voting Rights Act of 1965 should be scrapped, as a constitutionally unnecessary vestige of the civil rights era.

Known as Section 5, it gives the federal government open-ended oversight of states and localities like Shelby County with a history of voter discrimination.

Any changes in voting laws and procedures in the covered states must be "pre-cleared" with Washington. That could include something as simple as moving a polling place temporarily across the street.

The provision was reauthorized by Congress in 2006 for another 25 years and Shelby officials subsequently filed suit, saying the monitoring was overly burdensome and unwarranted.

This case will be one of the biggest the justices tackle this term, offering a social, political, and legal barometer on the progress of civil rights in the United States and the level of national vigilance still needed to ensure minorities have equal access to the election process.

Oral arguments will be held Wednesday, with a ruling expected by June.

Test of federal authority

Civil rights groups say Section 5 has proven an important tool to protect minority voters from local governments that would set unfair, shifting barriers to the polls. If it is ruled unconstitutional, they warn, the very power and effect of the entire Voting Rights Act would crumble.

But the provision's opponents counter it should not be enforced in areas where it can be argued racial discrimination no longer exists.

The appeal presents the court and its shaky conservative majority with two of the most hotly debated issues in politics as well as constitutional law -- race and federalism.

It will be a major test of Washington's authority, and the extent to which the central government may consider vestiges of voting discrimination that may still linger, potentially keeping some minority voters disenfranchised.

The Voting Rights Act was a monumental political achievement during the Civil Rights era. It banned such things as poll taxes and literacy tests that had long suppressed black voter turnout. States like California and Texas also have a history of discrimination against Hispanic voters.

In upholding the coverage requirements, the high court in 1966 succinctly summarized the law's purpose: "Congress felt itself confronted by an insidious and pervasive evil which had been perpetuated in certain parts of our country through unremitting and ingenious defiance of the Constitution," said the ruling. "Congress concluded that the unsuccessful remedies which it had prescribed in the past would have to be replaced by sterner and more elaborate measures in order to satisfy the clear commands of the Fifteenth Amendment."

The act was to expire in 2007 but was extended by Congress to 2032. It places all or parts of 16 states -- mostly in the South with a record of past discrimination -- under strict requirements on election procedures.

The Justice Department will defend continuing use of the pre-clearance provision in oral arguments, but the NAACP has led the charge to raise public awareness of the case.

"Closing off the paths to the polls and by trying to deter people from voting is too often practiced and trained and focused on minority communities," said Debo Adegbile, special counsel with the group's Legal Defense and Educational Fund, who will also argue before the justices in this case. "It doesn't happen everywhere but it happens too much."

Shelby County is 11 percent African-American, compared with 28 percent statewide.

Frank Ellis and his family have deep roots there, a former state senator and the county attorney for a half-century. His son, Corley, serves on the nine-member, all-white county commission.