It is a common occurrence for taxicabs to quickly stop or change lanes to pick up fares. The Chicago Municipal Code specifically provides that motor vehicles overtaking (legalese for passing) a bicycle may not then turn right in front of the bicyclist. In short, it is illegal to pass a bicyclists just to cut him/her off in order to turn. Here is the exact language from the ordinance:
9-16-020-f Turning right in front of a bicycle
When a motor vehicle and a bicycle are traveling in the same direction on any highway, street, or road, the operator of the motor vehicle overtaking such bicycle traveling on the right side of the roadway shall not turn to the right in front of the bicycle at that intersection or at any alley or driveway until such vehicle has overtaken and is safely clear of the bicycle.
Added Coun. J. 3-12-08, p. 22783
