When the year 2006 came, the RL made history by being the first Acura vehicle to be able to offer an optional Collision Mitigation Braking System (CMBS). This feature is considered to be a revolutionary safety technology, which monitors the potential rear-end collisions. It makes use of audio, visual and tactile signals in order to alert drivers of the risk of collision. It assists in brake operation as well as the tension in front seatbelts. In so doing, it helps reduce impact on occupants and vehicle damage, in such circumstances where the collision become unavoidable. Unlike other pre-collision systems, the CMBS automatically applies the brakes to mitigate the severity of a collision.

The CMBS system monitors the distance between the RL and the car directly in front of it up to a distance of 300 feet and the rate of closure between the two vehicles with the use of a millimeter-wave radar unit located inside the front grille. In case the closing rate increases to a point where a collision is likely to occur, the system uses visual, and olfactory warnings to set off the driver to take preventative action. Basing on the driver's response, the system will then determine if the possibility of a collision has decreased to an acceptable level. If so, the CMBS system will disengage. However, if response of the driver does not sufficiently reduce the risk of a collision, the system will issue a secondary warning. This consists of audible, visual and tactile elements as well as light braking, to alert the driver to take action.

And when the closing rate increases so much that a collision already becomes unavoidable, the CMBS can initiate hard braking to reduce the vehicle's speed. This also strengthens the tension on the driver's and front passenger's seatbelts, which help reduce the gravity of the crash.