What should I do with this Careless Driving ticket?

I think it really depends on the state you live in because there are so many different laws. In my state, it's no fault. Based on the fact that multiple cars were involved, I think you may have a hard time fighting it. I'd imagine they'd tell you that it's your responsibility to be keeping a safe distance from the car in front of you. It wouldn't hurt to try fighting it, but it depends on your excuse. I wouldn't go to court saying you caused the accident because you weren't looking in front of you. It's good you were checking your blind spot, but you also need to be aware of the space between you and the car in front of you. Other than icy roads, I'm not sure how you could really put together a solid argument. But I guess it couldn't hurt on a $427 ticket. Good luck!