Here is a news article on the issue. An excerpt:
State Rep. Kevin Killer, whose district represents the Pine Ridge Indian Reservation, said people do use the language services.
“We do have fluent Lakota speakers that do vote, and their preference is to have an interpreter there,” said Killer, D-Pine Ridge. “It’s better to err on the side of caution rather than make an assumption that nobody speaks Lakota.”
Fewer than 6,000 of the 120,000 members of Sioux tribes, who often identify themselves as Lakota, speak the language or its less common but closely related Dakota dialects. The average age of a Lakota speaker is 60, according to the Lakota Language Consortium.
But tribal schools such as Oglala Lakota College, Sinte Gleska University and Sitting Bull College have been reintroducing Lakota to a new generation through the schools’ language immersion programs, Killer said.
“So they’re going to be, at some point, hopefully fluent speakers,” he said.
Poll workers on Todd County’s Rosebud Indian Reservation have had to publish ballots in both English and Lakota and reprogram the AutoMark voting machines for each election, said Tripp County Auditor Kathleen Flakus, who also supervises the neighboring county.
Read more at the Washington Examiner: http://washingtonexaminer.com/news/2011/10/election-language-help-waived-sd-counties#ixzz1bKYV4wKo