To tell you the truth, I probably wouldn’t kill one if I found it here in the yard. I’d probably catch it and take it over to the state land and turn it loose. I would be sure to let my neigbors know to keep an eye out because they have kids that play in the yard.
The only native lizard we have in Michigan is the 5 lined skink and I’ve only seen two of those in nearly 46 years. As I understand it, they aren’t terribly rare, just secretive and quick. Kinda like fox.