is an opinion-page columnist for the Kansas City Star

The 2010 U.S. Census will soon be upon us, and by now you may have heard one of the patriotic pitches to comply.

The census is central to the functioning of our democracy, we're told. The data are used to distribute $400 billion in government spending, report on educational needs, plan for economic development, and formulate policy.

More important, census data have a direct bearing on congressional districts. The information helps us uphold the constitutional principle of one person, one vote.

So why, then, is the federal government gearing up to distort this vital set of data by how it accounts for the nation's booming prison population? Prisoners are counted not according to their home addresses, but where they are incarcerated. At a glance, this might not seem like a big deal - until the details that apply to our nation's two million inmates are broken down.

Rural communities with large prison populations suddenly appear to be bastions of diversity, while those without prisons continue to see their population numbers slide. On average, inmates serve for 34 months before returning to their original communities. They never shop, dine, attend school, or otherwise become involved in the towns and cities where they are incarcerated.

One distortion caused by this method of counting is what some activists call "prison-based gerrymandering." Because population figures are used to determine legislative districts, voting power is diluted in some areas and falsely ramped up in others. Because 12 percent of black men in their 20s and 30s are in prison at any one time, urban areas lose out on the strength of those uncounted inmates.

But rural communities, where prisons are often built, suffer the most from the distortions. Peter Wagner, a Massachusetts-based advocate for the Prison Policy Initiative, has found 173 counties where more than half of the black population is made up of inmates. Seven state Senate districts in New York alone, he argues, would need to be redrawn if inmates were omitted from population figures.

Local officials in some parts of the country have responsibly attempted to eliminate the distortions. Bravo. Anamosa, Iowa, changed the way it elects city council members after discovering that one candidate's inmate constituency of about 1,300 prisoners was roughly as populous as the town's other wards.

With census takers already completing the process of verifying addresses for the spring head count, it's too late for the government to change plans for 2010. Recording the true home address of inmates would be costly (an estimated $250 million), and many prisons don't have the information readily available. What the government can do is release the prison data earlier than planned, in time for states to take the information and delete those numbers for redistricting purposes.

Criminals forfeit a lot when they get locked up. They lose the right to vote in all but two states. They lose daily interaction with loved ones and the chance to engage in meaningful work. What they shouldn't lose is the sense that their presence counts.