(2) The person has a previous conviction under:
a. Subsection (a1) of this section;
b. Subsection (a5) of this section; or
c. G.S. 14-17 or G.S. 14-18, and the basis of the conviction was the unintentional death of another person while engaged in the offense of impaired driving under G.S. 20-138.1 or G.S. 20-138.2.
The pleading and proof of previous convictions shall be in accordance with the provisions of G.S. 15A-928.
A person convicted under this subsection shall be subject to the same sentence as if the person had been convicted of second degree murder.
Unless the conduct is covered under some other provision of law providing greater punishment, the following classifications apply to the offenses set forth in this section: