https://www.nytimes.com/2020/08/27/u...ing-video.html
This is a good breakdown of the sequence of events in the Rittenhouse shootings.
First, at best Rittenhouse is a complete idiot. If he thought driving into a situation like that with an assault rifle would help keep the peace then he's got no sense at all. Considering he was obsessed with police and was walking around with a med pack, it makes me think he thought of himself as some sort of vigilante peacekeeper. However, this is someone I wouldn't trust with a spoon much less an assault rifle.
Second, I'm going to try to look at this objectively and how the law might work in this case.
Here we go. The prosecution is going to have a difficult time on this one. According to that NY Times article, Rittenhouse was being pursued by a crowd before the first shooting and someone in the crowd fired a gun into the air. That could make a murder conviction tough. He's one person allegedly being pursued by multiple people. Someone has fired a shot already and another person is lunging at Rittenhouse. It's not going to be easy to get a murder conviction there.
However, a lot could depend on the facts of how this altercation started. If it comes out that Rittenhouse had been waving his gun around threatening these people then their reaction to that might be reasonable and so defeat Rittenhouse's self defense claim. Running counter to that and something his lawyers will bring up is Rittenhouse may have been retreating. If he was retreating from a prior altercation and was being pursued, it changes things.
The second and third shootings are even dicier as far as getting a conviction goes. The video shows a large group pursuing Rittenhouse down the street. At least one of the pursuers appears to be carrying a handgun. Rittenhouse falls to the ground and things deteriorate from there. It looks like someone tries to grab his gun at some point and fails. Two people are shot, one of which appears to be armed (again, going by the NY Times article). Someone being pursued by an armed mob and who falls to the ground might be in reasonable fear for their life or safety.
Where it could go against Rittenhouse in the second shooting is if he's in the wrong in the first. If the first is murder then there's the argument that the crowd was trying to stop a murderer from escaping. Wisconsin, best I can tell, does have a citizens arrest doctrine. If the crowd was in the right making a citizens arrest of a murderer then Rittenhouse doesn't have the right to open fire on those apprehending him.
Bottom line, this is not a clean case by any measure. The videos aren't super clear and there are still a lot of holes in the sequence of events. Self-defense is this kid's only real hope though.