This is one of the most common motorcycle collision scenarios. Generally, the vehicle turning left—often at a traffic light or stop sign—fails to yield to oncoming traffic. They may not check for traffic, or they may look but fail to see the motorcyclist because they were expecting a larger car.
In most cases, the car turning left will be considered at fault in this type of accident. The driver should have been watching the roadway and yielding to oncoming traffic. Failing to do so is a violation of the law.
However, it is important to realize that, in some cases, it might be possible to prove that they were not at fault. This is usually true of cases in which you, as the motorcyclist, were speeding, texting, or had run a red light. In some situations, each party may be assigned a percentage of fault depending on how responsible they were for what happened.