Legal Question in Civil Litigation in California

Re: Are they Responsible

If you could prove they did it on purpose, perhaps. But, I highly doubt that is the case... and even if it is, it would be difficult.

I don't think the owners of the garage would be held to a duty of care to make sure that there isn't a dolly outside of their garage before opening. The duty is yours.

Re: Are they Responsible

Nothing in your post indicates they acted intentionally and can't imagine any reason why you think the would even be remotely responsible.

Re: Are they Responsible

Liable? For what? For opening their own garage door? Unless the husband did this intentionally in order to hit your dolly, the answer is no.

Has it occurred to you that you and your friend might actually be the ones who are responsible, since you were the ones who carelessly left the dolly where an opening garage door might strike it? It isn't your neighbors' fault that you did this, and they are not required to inspect the driveway every time they open their garage door. Do you perform that kind of inspection every time you open yours?

The fact that the husband opened the door accidentally rather than on purpose is irrelevant. He has a right to open his door whenever he wants (or even when he doesn't, as happened here) unless he knows that doing so will harm someone. Since he did not intend to open the door, there is no reason to believe he had any idea what the effect of opening it would be or that he intended to cause any harm.

Too many people think they can turn to the law whenever they want to hold someone else responsible for their own mistakes -- which is what you evidently want to do as well. The law doesn't work that way.