The iCar probably won't actually mow anyone down. More likely, it will suddenly brake in order to avoid what it wrongly perceives as a pending accident, then get rear-ended by other driver(s) who did not expect someone to suddenly stop in the middle of the road. When one of those happens and the driver(s)/passenger(s) of the tailing vehicles are killed, it will be considered their fault for following too closely, paying too little attention, and tragically crashing into the Apple Car/Blackberry Car/etc.
If America can guarantee one thing, it's product accessibility. Felons with drugs? Check. Octogenarians with three hundred horsepower sport utility vehicles? Check. Half-blind post-stroke nonagenarians with fifty-foot recreational vehicles, which are themselves towing personal vehicles, barreling past school buses on field trips? Check. Paraplegics with elaborate prostheses to allow them to drive their very own car to Best Buy? Check. Illiterate people with subsidized smartphones? Check. Health, safety, sanity, fiscal responsibility--none of these things matter. "Smart cars" sound a little like a terrifying robotic future, but they're really not. They'll just be another set of incompetent drivers. Incompetent drivers don't actually get in most of the crashes--they cause the crashes, but they don't get in them. They don't appear in the statistics, or the morgue, in proportion to their driving ability. They cause accidents by erratic swerving and breaking that results in other drivers crashing into them, or, more often, that results in other drivers maneuvering away from the idiots' obstructions, and hitting one another, leaving the guilty vehicle unscathed. Because they're overwhelmed and confused by the natural flow of traffic, low-competency (robotic) drivers create obstructions that others avoid to others' detriment. E.g., they idle in travel lanes, blinker running, causing others to brake hard or attempt sudden passes; they turn in front of bikers, causing bikers to swerve into pedestrians or other traffic; they hesitate on the verge of traversing intersections, causing everyone in the surrounding area to shimmy and shudder in potential anticipation; they create auras of weirdness and flow-disruption that can radiate blocks, or even miles, in all directions, as their unpredictable rates of acceleration and deceleration cause cascading patterns of braking, speeding up, stacking at lights/corners, or inciting lane changes.
Smart cars will do the same: they will be very formal, proper, ultra-safe drivers, who brake hard when a large leaf, or a loose section of cardboard, crosses their sensor array. All of the "good" drivers in the vicinity will react appropriately to the leaf/cardboard, but when Mr. Pichai's sedan "avoids the collision" by applying expert braking maneuvers when a red balloon floats by the bumper, twelve people behind him will shriek, curse, slam, and wrench their wheels to either side. Mr. Pichai will either receive damage to his rear bumper, or drive away shaking his head in consternation at all those "impatient risk-takers" behind him, who were so eager to rush to work that they "rode his ass" and caused a horrific pileup.
As with the thousands of yearly deaths, and hundreds of thousands of yearly injuries, caused invisibly by confused motorists unaware of all the people desperately trying to avoid them, the smart-car massacre will go unnoticed by history. Police reports, coroner's reports, lawsuits, settlements, insurance statistics, newspaper articles: all will be able to draw only upon the hard data of "who died" and "who hit what," unable to take into account the complexities of abstract dynamics that produce the erraticisms that end in tragedy. It is just too cruel, too unfair, says the feds/Fed, that competency requirements include more than "Point A to Point B, obeys signals and stops for obstructions."
Like prior poor drivers, smart cars will occasionally have cognitive errors that cause them to suddenly floor it in the parking lot of the local grocer, run down four bystanders, and crash terminally into lampposts--but the full extent of their havoc will never be provable. All the policies that we have in place right now to mandate the "everyone is a licensed pilot" standard, which so effectively designs an inefficient society in thousands of ways, were produced, of necessity, in order to encourage ongoing fees, lowest common denominator barriers, and recurrent damage, and to channel anger at the system's problems toward attempts to fix the system.