Starboard boat capsizing onto port boat

Originally posted by A Seabadger

Originally posted by A Seabadger

Isn't it a case of having "time and opportunity" to keep clear. As you didn't have either despite your best efforts you are not in the wrong. 

In 30kts, 'keeping clear' might oblige the port boat to keep a safe distance from the stbd boat. 
The stbd boat is not capsized until the masthead hits the water, but remains right of way the whole time.
You had time and opportunity to tack or bear earlier off to keep a sensible distance from the right of way boat.
There are very few excuses for collisions. One or both boats is always in the wrong.