Section 2. Except as herein otherwise provided, the driver of a vehicle passing another vehicle traveling in the same direction shall drive a safe distance to the left of such other vehicle and shall not return to the right until safely clear of the overtaken vehicle; and, if the way is of sufficient width for the two vehicles to pass, the driver of the leading one shall not unnecessarily obstruct the other. If it is not possible to overtake a bicycle or other vehicle at a safe distance in the same lane, the overtaking vehicle shall use all or part of an adjacent lane if it is safe to do so or wait for a safe opportunity to overtake. Except when overtaking and passing on the right is permitted, the driver of an overtaken vehicle shall give way to the right in favor of the overtaking vehicle on visible signal and shall not increase the speed of his vehicle until completely passed by the overtaking vehicle.
The driver of a vehicle may, if the roadway is free from obstruction and of sufficient width for two or more lines of moving vehicles, overtake and pass upon the right of another vehicle when the vehicle overtaken is (a) making or about to make a left turn, (b) upon a one-way street, or (c) upon any roadway on which traffic is restricted to one direction of movement.
Structure Massachusetts General Laws
Part I - Administration of the Government
Title XIV - Public Ways and Works
Section 2 - Passing Vehicle Traveling in Same Direction
Section 3 - Sleigh or Sled; Bells
Section 4 - Keeping to Right While View Obstructed
Section 4a - Driving Vehicles in a Single Lane; Motorcycles, Riding and Passing
Section 4b - Driving in Lane Nearest Right Side of Way
Section 4c - Heavy Trucks; Driving in Right-Hand Lane on Multi-Lane Highways
Section 4d - Standing or Parking of Motor Vehicle in a Designated Bike Lane
Section 5 - Penalty; Exceptions
Section 6 - Applicability of Rules of Road to Street Railway Cars
Section 6a - Stopping of Street Railway Cars for Passage of Fire Apparatus
Section 7 - Right of Way of Fire Engines, Patrol Vehicles and Ambulances; Obstruction; Penalties
Section 7a - Restrictions on Use of Ways Upon Approach of Emergency Vehicles
Section 7b - Operation of Emergency Vehicles
Section 7d - Moving of Vehicle Involved in a Crash From a Travel Lane
Section 8 - Right-of-Way at Intersecting Ways; Turning on Red Signals
Section 9 - Designation of Highways as Through Ways; Traffic Control Signs and Devices
Section 10 - Violation of One-Way Traffic; Civil Liability
Section 11 - Marked Crosswalks; Yielding Right of Way to Pedestrians; Penalty