South Dakota Codified Laws
Chapter 07 - Habitual Offenders
Section 22-7-8 - Three or more additional felony convictions including one or more crimes of violence--Enhancement of sentence.

22-7-8. Three or more additional felony convictions including one or more crimes of violence--Enhancement of sentence.
If a defendant has been convicted of three or more felonies in addition to the principal felony and one or more of the prior felony convictions was for a crime of violence as defined in subdivision 22-1-2(9), the sentence for the principal felony shall be enhanced to the sentence for a Class C felony.

Source: SDC 1939, §13.0611; SDCL, §22-7-1; SL 1976, ch 158, §7-3; SL 1977, ch 189, §19; SL 1981, ch 13, §4; SL 1984, ch 166, §1; SL 2005, ch 120, §384.