FORT COLLINS, Colo. (AP) — A woman who donned a black mask, ordered her ex-lover's wife to her knees and shot her twice in the head was convicted of murder and sentenced to life in prison without parole Monday.

"You carried out this plan with great planning and deliberation," Judge Roger Klein told Shawna Nelson. "You deserve to serve every day of the sentence I will impose."

Nelson showed little emotion as the verdict was read and declined the judge's invitation to make a statement before he handed down the sentence. Her attorneys said they will appeal her conviction.

Nelson killed Heather Garraus, 37, on Jan. 23, 2007. A Weld County sheriff's dispatcher at the time, Nelson had a long affair with Garraus' husband, Ignacio, who was a Greeley police officer.

They had a son together, but Ignacio Garraus broke off the relationship a month before the shooting.