Based on the Ford Fusion Hybrid, it has "full pursuit" capabilities, and runs on the battery only below 60 mph, depending on the charge (Ford didn't specify the lithium-ion battery's capacity, but it doesn't appear to be the plug-in model). That's backed up by an Atikinson-cycle 2.0-liter engine that puts out 141 horsepower in the stock Fusion configuration.

It will go into pursuit mode when the throttle is held down for five seconds, engaging both the gas and electric motors. While not as quick as the 3.7-liter turbocharged Taurus-based Interceptor, Ford figures it'll be fast enough to earn law enforcement's "pursuit" rating.

With a 38 mpg rating compared to 18 mpg combined for the current car, Ford figures it'll save around a quarter-gallon of gas per hour, amounting in up to $3,900 a year in savings. At the same time, it's "certified by police agencies to be tough enough to handle police pursuits for longer periods at different speeds and over obstacles such as curbs and flooded intersections," Ford writes.

Law enforcement groups are interested in the Police Responder's economy, but concerned about its reliability. "Anytime you can save money it is good," Michigan-based Police Chief Thomas Korabik told the Associated Press. "I'd want to see the car first and see how it would hold up." He also wondered whether it's big enough to handle the computers and other equipment now hosted by most police cars.