A record number of Americans with criminal records cannot vote in what is expected to be a tight presidential election, a new study says.

More than 5.85 million adults who've been convicted of a felony aren't welcome at polling places, according to data through 2010 compiled by The Sentencing Project. That's 600,000 more than in 2004, the last time the nonprofit group crunched the numbers.

The vast majority of these disenfranchised adults have been released from prison. Sentencing Project researchers found more than 4 million Americans who cannot cast a ballot because they're on probation or parole, or live in a state that withholds the right to vote from all ex-felons.

"This is a fundamental question of democracy," said the Sentencing Project's executive director Marc Mauer. "These policies go back to the founding of this country. [The U.S.] was founded as a great experiment in democracy, but was very limited. Wealthy, white male landowners granted themselves the right to vote, but women, poor people, African Americans and people with felony convictions could not vote.

"This is the last fundamental group that's still excluded from democratic participation."

A majority of felons and ex-cons blocked from voting reside in a core of six Southern states -- Alabama, Florida, Kentucky, Mississippi, Tennessee and Virginia -- where more than 3 million people are banned from the rolls.

Punishing people with felony records hits African Americans harder than other races: 7 percent of blacks are disenfranchised compared to 1.8 percent of the rest of the country, the study found. The numbers are more drastic in Florida and Virginia, political battlegrounds considered crucial in deciding the outcome of November's election. In Virginia, 20 percent of blacks can't vote. In Florida, that number is 23 percent. President Obama carried both states in 2008. (Kentucky, which is safely in Republican hands, is the only other state where 1 in 5 African Americans can't vote.)

Reliable information for Latinos wasn't available, according to Christopher Uggen, the lead author of the report. Uggen said that Hispanics are disenfranchised at a rate higher than whites, but lower than blacks.

"There's no question this has a basis in race discrimination," ACLU Voting Rights Program director Laughlin McDonald told The Huffington Post. "It's part of the history of the racial minorities in the South. The Southern states adopted a whole variety of measures to take away the right to vote after Reconstruction."

Excluding criminals from voting goes back even further, according to the National Conference of State Legislatures. In ancient Greek and Roman societies criminals experienced "civil death," a punishment that could entail loss of property and the right to sign contracts, as well as vote.

Current rules about who can vote vary greatly from one end of the country to the other. Maine and Vermont are the only states permitting felons to vote from behind bars. Eleven states take away the franchise for life, although some allow ex-felons to appeal for the right to be restored. Between the extremes are states with different rules for parolees and people on probation.

The general nationwide trend over time has been to loosen voting restrictions on current and former felons, although the number of disenfranchised voters continues to rise because more and more people are under some form of supervision by the criminal justice system.

Virginia, a state that disenfranchises felons for life unless they apply to get the vote back, instituted a program in 2010 that guarantees a quicker decision on restoration requests. Virginia Gov. Bob McDonnell (R) also shortened the period that a non-violent ex-felon must wait to apply from three to two years.

"Restoration of rights to citizens who have committed a crime, served their time, and returned to society is a top priority of this administration," said Jeff Caldwell, a spokesman for McDonnell, in a statement sent to The Huffington Post. "It is a goal of this administration to restore as many rights as possible to those who have paid their debt to society and returned to be productive citizens."

Moving in the opposite direction are Florida and Iowa, where incumbent governors reversed polices that granted more voting rights to people emerging from correctional supervision. Upon taking office last year, Republican Gov. Terry Branstad undid an executive order by his predecessor that permitted all former convicts to vote. Now, they must apply and prove they've repaid all court fees and restitution to victims. Florida Gov. Rick Scott (R) instituted a five-year waiting period before people who've served their sentences can apply to get the vote.

"We believe that the victims need to be taken into account," said Branstad's spokesman Tim Albrecht. "The governor does not believe that felons should have a blanket restoration of their voting rights."

The number of Americans denied voting rights continues to grow despite the general easing of barriers to voting for people with criminal records. In 1976, there were fewer than 1.2 million disenfranchised Americans. The researchers link the unrelenting growth in disenfranchised voters to the expanding number of people incarcerated or under some form of supervised release.

Of course, not every eligible voter actually participates on Election Day. In the last presidential election, 64 percent of voting-age people turned out at the polls, according to a Census Bureau report. It's difficult to estimate how many people with felony records would vote if they could. But it's probably far below average, because they tend to come from a lower-income, lower-education demographic that votes less, experts said.

'When people first come out, they have a lot of central surival concerns and voting is probably not high on their list," said Ann Jacobs, director of the Prisoner Reentry Institute at John Jay College. "But as you get your life more stable, self-expression through voting becomes a higher priority."

Still, the number of excluded voters could be decisive for a candidate.

"The numbers are quite substantial," the Sentencing Project's Mauer said. "In a close contest, whether for city council or the U.S. Senate, [it] could affect an election."


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