Section 811.500 - Unlawful stop or deceleration; penalty(1) A person commits the offense of unlawful stop or deceleration if the person is operating a vehicle and the person stops or suddenly decreases the speed of the vehicle without first giving an appropriate signal to the driver immediately to the rear when there is opportunity to give the signal.(2) Appropriate signals for the purpose of this section are as designated under ORS 811.395 and 811.400.(3) The offense described in this section, unlawful stop or deceleration, is a Class B traffic violation.1983 c.338 §657; 1995 c.383 §77