Matthews was shot 14 times by Spearman in a dispute over electricity being turned off, according to Maria Miller, a spokeswoman for Wayne County Prosecutor Kym Worthy.
The case was unsolved for 18 years but reopened in January 2020 by the Michigan State Police 2nd District Special Investigation Section after new witnesses came forward, Miller said.
Harris pleaded guilty on Oct. 8 and was sentenced to 10-20 years on Nov. 2.
Spearman pleaded guilty on Dec 4 was sentenced on Jan. 22 to 15-30 years.
Contact Nour Rahal at nrahal@freepress.com and follow her on Twitter @nrahal1.
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