The problems with introducing driverless cars are greater than you identify in your editorial (Intelligent cars raise questions that only society can answer, 16 December) and yet almost certain to be ignored.

No amount of testing can prove them as safe as human drivers unless the software is frozen and never updated Professor Martyn Thomas

No amount of testing can prove them as safe as human drivers unless the software is frozen and never updated. Verifying the behaviour of machine-learning systems is an unsolved research challenge. There are major problems of cybersecurity – many of the sensors and communications have already been hacked. Who would risk being a passenger alone, when anyone can easily force the car to stop?

But politicians are probably powerless to prevent the sale and use of these cars when multinational companies are investing billions of dollars and countries are competing for a share of the investment, tax revenues and other benefits. When one region has driverless vehicles on the street, how will others resist the pressures to follow suit? Yet the real dangers may only arise after there are fleets of driverless cars on the roads, when a cyberattack allows a criminal or terrorist to control hundreds or thousands of vehicles, gridlock a city, deliver bombs, or distract and obstruct emergency and security services while some other crime is being committed.

These scenarios should be considered and researched, and countermeasures should be devised with urgency, so that the necessary constraints on the software and hardware of driverless cars can be imposed internationally before fleets of such vehicles present a threat that cannot easily be overcome.

Professor Martyn Thomas

Gresham College, London

• Part of the driverless futuristic nightmare – and job losses – could come from platoons of lorries linked and controlled electronically by the first HGV and driver with the rear lorries driverless (Why the driverless future could turn into a nightmare, 16 December). The reality is that the government plans to trial processions of lorries, which could be vulnerable to cybercrime, even though our motorway network is congested, with frequent exits close together. Instead, why not use a freight train which is much safer, far less polluting, and can individually remove up to 136 HGVs?

Philippa Edmunds

Freight on Rail manager, Campaign for Better Transport

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