If a bike rider is traveling in the right lane or bike land alongside parked cars, who is legally responsible when car door-bike collision occurs?
Most areas have laws that require car users to check for bicyclists before opening the door of their vehicle, but there have been serious injuries and deaths caused by drivers illegally opening their doors in the path of a passing cyclist where this is prohibited by law.
Many areas have laws allowing cyclists to ride in the door zone, meaning they may expose themselves to danger in order to keep out of the way of motorized traffic. These laws typically have exceptions; avoiding hazards, such as an open door, is sometimes among them.
The so-called "door zone" is the space in which a cyclist is in danger of getting hit by a car door. It varies depending upon the model of car one is riding by. It can be almost zero when riding by a vehicle with gull-wing doors or much larger if one is riding by a truck.
Some local ordinances spell it out clearly. For example, in my hometown of Bellingham, Wash., the law for this is spelled out in RCW 46.61.620:
"Opening and closing vehicle doors - No person shall open the door of a motor vehicle on the side adjacent to moving traffic unless and until it is reasonably safe to do so, and can be done without interfering with the movement of other traffic, nor shall any person leave a door open on the side of a vehicle adjacent to moving traffic for a period of time longer than necessary to load or unload passengers."
Things get a bit murky sometimes as laws in some jurisdictions indicate to ride as far to the right as possible in a safe mode. One is sharing the road with other passing cars and trying to avoid opening car doors at the same time can be in conflict.
I would recommend to always ride with a mental red flag that a parked car door could swing open at any time. I try to look if I can see anyone in the driver's seat as I approach. If there is, I assume that the drive may not be aware of my approach and I proceed cautiously. Riding at full speed alongside parked cars is not a good idea. Most of the time, all will be well, but every now and then, there is a painful exception...If there is a bike lane outside the door zone, it is safer situation. During my West Coast tour I only encountered the parked car door opening issue in bigger cities, especially in Southern California. Another problem area is along roads which beach access where cars often pull over and park on the side of the road. This is where I encountered my only close call where a beach goer parked mostly off the road and swung open the door in as I was approaching. Fortunately, I had slowed down in this area and was able to avoid the collision.