It happened just after 3 a.m. Friday morning on Eastbound Highway 168 near Shaw Avenue.
The CHP says a man in his 40s was on eastbound 168 near Shaw when the driver of an Infinity, Perla Vazquez, rear-ended him and sent him off the freeway, where he plunged at least 40 feet down an embankment.
The CHP also said a short time later, an off-duty Madera police motorcycle officer saw the suspect vehicle with heavy damage and pulled the driver over and called for help.
The CHP says the driver of the Jeep that went off the road has died.
Vazquez was arrested for D.U.I, hit and run, and murder charges.
The identity of the victim has not been released.