Thelma Rios, a member of the Oglala Sioux Tribe of South Dakota, entered a not guilty plea in connection with the 1975 murder of American Indian Movement activist Anna Mae Pictou Aquash.

Rios, 64, is charged in state court with one count of felony murder in relation to kidnapping and one count of premeditated murder. Rios is accused of holding Aquash at a home in Rapid City, prior to Aquash being killed on the Pine Ridge Reservation.

John Graham, 53, a Native man from Canada, faces similar charges. South Dakota Attorney General Marty Jackley, who handled the Aquash case when he was serving as U.S. Attorney for South Dakota, filed the charges last month after the 8th Circuit Court of Appeals said Graham couldn't be tried in federal court because he is not an "Indian" under U.S. law.

Get the Story:
Woman arraigned for 1975 killing (KEVN-TV 10/6)

8th Circuit Decision:
US v. Graham (July 28, 2009)

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Two indicted in state court for Aquash murder (09/11)
Aquash defendant to face state court charges (9/10)
Prosecutors want delay in Aquash murder trial (9/9)
Judge won't dismiss Aquash murder indictment (9/8)
Trial set for remaining Aquash murder defendant (8/4)
Appeals court dismisses charge in Aquash case (7/28)
Aquash murder defendant seeks separate trial (7/22)
Aquash murder trial delayed until appeal resolved (5/6)
Hearing scheduled for Aquash murder defendants (5/5)
Case against Aquash murder defendant coming apart (5/1)
Judge rejects probe into BIA informant claim (4/30)
Trial for Aquash murder defendants set to begin (4/27)
8th Circuit hears Indian status appeal in Aquash case (8/16)
Aquash murder defendant seeks release until trial (4/10)
BIA official's link to informant raised in Aquash case (4/1)
8th Circuit to hear appeal in Aquash murder case (3/23)
Trial for Aquash murder suspects delayed again (3/3)
U.S. Attorney opposes separate Aquash trials (12/16)
Aquash murder defendant seeks separate trial (12/1)
Prosecutors seek to bolster Aquash murder case (11/11)
Prosecutors defend charges in Aquash murder case (11/3)
Aquash murder defendant raises 'Indian' issue (10/27)
Trial for Aquash murder delayed to February 2009 (10/20)