It would seem he may be fucked for possessing the gun if he really is under 18.

Illinois or Wisconsin both have minimum age of 18.

If he was committing a crime of possession, can he be charged for the deaths while doing it?

If he was 18 it would be clear cut self defense.

The age of 17 could add a pretty big twist.

Spez: Maybe not!

https://www.jsonline.com/story/news/crime/2020/08/26/wisconsin-open-carry-law-kyle-rittenhouse-legally-have-gun-kenosha-protest-shooting-17-year-old/3444231001/

It would seem he may be fucked for possessing the gun if he really is under 18.

Illinois or Wisconsin both have minimum age of 18.

If he was committing a crime of possession, can he be charged for the deaths while doing it?

If he was 18 it would be clear cut self defense.

The age of 17 could add a pretty big twist.