The bill still needs to be approved by the House of Representatives before it can become a law.

The United States Senate has just passed a bill that aims to make data recorders mandatory in all cars starting in the 2015 model year.

The bill, called "Moving Ahead for Progress in the 21st Century Act", needs to be approved by the U.S. House of Representatives before it can become a law.

Some of the bill's opponents have said that it is a way to invade the privacy of motorists. The bill addresses this issue and clearly states that any data stored in the recorder will be the sole property of the car's owner. If the car is leased, the data will belong to the lessee.

However, recorded data will be accessible by someone other than the owner if a court order is issued, if it is needed for a police investigation or if it is needed by emergency medical workers in the event of an accident. The owner of the car will be able authorize anyone to access the data for any reason.

The bill does not specify what data the recorder will need to store. Elements that are likely to be retained include the speed and roll angle of the vehicle, the time of airbag deployment and the throttle position.

Data recorders (often called black boxes) have been found in a lot of new cars for years but they were put there by the automakers by choice, not by law.