SDCL § 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.