In Massachusetts, it is very common to see traffic tickets for failing to move left when an emergency vehicle is on the side of the road. This is a violation of the "Move Over Law". Under Massachusetts General Laws Chapter 89 Section 7C:

(b) Upon approaching a stationary emergency vehicle, highway maintenance vehicle or recovery vehicle with flashing lights an operator shall:

(1) proceed with due caution, reduce the speed of the vehicle to that of a reasonable and safe speed for road conditions, and, if practicable and on a highway having at least 4 lanes with not less than 2 lanes proceeding in the same direction as the operator's vehicle, yield the right-of-way by making a lane change into a lane not adjacent to that of the emergency response vehicle, highway maintenance vehicle or recovery vehicle; or

(2) if changing lanes is impracticable, proceed with due caution and reduce the speed of the vehicle to that of a reasonable and safe speed for road conditions.

(c) Violation of this section shall be punished by a fine of not more than $100.

The Massachusetts police take this violation extremely seriously, because of the danger to the officer or other emergency personnel that may be on the side of the road.  Due to the inherent danger, it is very common to see a violation still given even when the operator slows significantly, but does not pull to the left lane.  

Because of this, if you see an emergency vehicle on the side of the road, pull over to the left lane at your earliest opportunity.  If you are unable to do so and receive a citation, contact Broadbent Law to contest the citation.