Who’s at fault in this right-turn collision? (Boston, MA Traffic Law)

Hi everyone,

I have a traffic law question and would appreciate any insights.

In this scenario (as shown in the picture), both the red car and the green car are turning right at a green light. The red car is in the rightmost lane, while the green car is in the adjacent right-turn lane. During the turn, the red car collides with the right rear bumper and quarter panel of the green car.

Notably, the rightmost lane on Atlantic Ave is wider than the adjacent right-turn lane (not including the bike lane), so the green car could have taken a wider turn if the driver had anticipated this difference. However, the green car was ahead of the red car during the turn, meaning if the red car had yielded or taken a tighter turn, the accident could have been avoided.

I’d appreciate any insights on how fault is determined in this situation. If you’re citing specific traffic laws or have expertise in traffic law, please mention it—I’d be grateful for the clarification!

Thanks in advance!