The Brennan Center issued a study today about voting technology and residual votes. The key take-aways are that both DREs and precinct-count optical scan are systems that produce low residual vote rates and full-face machines, like those contemplated in New York, are terrible.

As the press release for the report states:

Significantly, several studies indicate that residual vote rates are higher in low income and minority communities. The Brennan Center study shows that improvements in voting equipment and ballot design produce substantial drops in residual vote rates in such communities. As a result, the failure of a voting system to protect against residual votes is likely to harm low-income and minority voters and their communities more severely than other communities. Among the report’s key findings:

* Precinct Count Optical Scan (PCOS) and scrolling Direct Recording Electronic (DRE) voting systems are more accurate at recording voter intention than older voting systems. In 2004, residual vote rates were less than 1% for both technologies.

* Full-face DRE systems continue to be plagued with an unacceptably high residual vote rate. In 2000, 2002 and 2004, it exceeded that of either PCOS or scrolling DRE systems.

* Residual vote rates among voters earning less then $25,000 are higher on full-face DRE’s ( 2.8%), than on either PCOS (1.4%) or scrolling DRE’s (1.3%).

“The good news is that most states are selecting machines and designing ballots that will record more voters’ choices accurately. The bad news is that major jurisdictions like Philadelphia, and perhaps New York City, plan to use voting technology that is known to have high error rates,” said Lawrence Norden, Associate Counsel at the Brennan Center and lead author of the report.

The report can be downloaded here.