At the recent Liberal Democrat open-toed conference for people with cagoules, the party’s home affairs spokesman Mark Oaten stood on the podium and made a table-thumping speech about the dangers of proposed legislation that would outlaw the glorification of terrorists. It would, he said earnestly, put “freedom of speech at risk”.

In other words he’s prepared to let fanatics shower praise on those who blew themselves up in the London bombings, because speaking your mind is a “clear and principled” Lib Dem policy. The bedrock of all they hold dear.

Right. So how come then that the Lib Dems’ transport spokesperson Tom Brake vigorously and publicly opposed my recent honorary doctorate from Oxford Brookes University? Interesting, isn’t it? The Lib Dems are happy for people to speak in glowing terms about suicide bombers and those who fly airliners into tall buildings. But they are emphatically not happy for anyone to speak in glowing terms about the motor car.

And that’s a pity, because what follows is a partly political road test on behalf of the Liberal Democratic party. Yes, I’m reviewing a car that seems to have been specifically designed for the world’s woolly-faced lunatic fringe. The people who put the mental into environmental. It’s called the Lexus RX 400h and it’s a hybrid.

So, it has a conventional V6 petrol engine that is used partly to drive the front wheels and partly to charge a set of batteries that are stored in a cooled chamber under the back seat. These power an electric motor that also drives the front wheels.

The idea is that when you put your foot down the electric motor and the V6 join forces to provide Herculean power. Lexus say it’s as powerful as a big V8, and certainly it shifts. It does 0-62 in 7.6sec, for heaven’s sake, which means its faster than the standard petrol version.

However, at slow speeds, when you’re trickling around town, the petrol engine shuts down completely and you run only on battery power. This means your car is as quiet as the bicycle you part-exchanged to buy it. It also means you are producing no exhaust gases.

Think of that. You can bring rainfall to the parched and end the cycle of hurricanes in the Gulf. You can repair the Antarctic ice shelf and bring cod once again to our waters. You can do up all those things which, we’re told, global warming has undone. You can buy a Lexus and mend the world.

The very idea will no doubt be causing those of you in sandals to masticate furiously. But you may be a little alarmed by the photographs because surely, you’re thinking, the car in question is an instrument of Satan, the Reaper’s scythe. The Bringer of Death. A 4x4.

Well no, most of the time the two engines in the front only power the front wheels, so when you’re pottering about town you needn’t have guilt. However, should you wish to drive off road so that you can interfere with a pheasant shoot, or place some rare snails in the path of a proposed bypass, don’t worry.

Because there’s another electric motor that automatically springs to life at times like this to drive the back wheels as well. Brilliant. That means the four-wheel-drive-ness of the nuclear-free peace-Lexus comes at no cost whatsoever to the planet. It’s an open-toed 4x4. A free-range SUV. The closest you can come to organic motoring.

Strange to report, then, that in Cornwall, where the Lib Dems hold every single seat, there isn’t a single Lexus dealership. So this must mean they’re expecting normal people to buy it as well.

And why not? I mean, if it runs partly on electrical power then this is every sane person’s dream machine as well — a 4x4 SUV that doesn’t need its own North Sea pipeline to get to town and back.

Better still, unlike old-fashioned electric cars you don’t need to plug this one into the mains at night — the engine charges the batteries for you. Also, apart from some complex hieroglyphics that pop up on the dash occasionally, there’s really no way of telling what’s driving what at any given time.

You just potter about quite normally, completely unaware that the engine is starting and stopping constantly. The only clue that you’re in something weird comes when you lift your foot off the throttle and coast.

You hear a faint hum as the wheels use their momentum to pump a little bit more juice into the batteries. Technically, it must be said, this car is brilliant.

The interior is nicely thought out as well with a charging point right next to the storage bin in which you’re bound to put your phone, and lots of storage bins for homework and Haribos. And my God it’s quiet. It’s so quiet in fact that you can hear the leather creaking and wind rushing in through a badly fitting door seal. Lexus quality? Not on this car there wasn’t.

Other drawbacks? Well there’s so much power that you get a bit of torque steer when pulling smartly away from a junction and, as I said when I tested the normal version, it doesn’t have a chunky feel, which is something I look for in a 4x4. There’s no sense that it would survive the battering of a hurricane, or that children won’t break all the interior fixtures and fittings within a day. It feels like a normal car. And it’s only as spacious as a normal car, too.

Happily, it’s also priced like a normal car. Even though it has three engines and all those rechargeable batteries and a huge amount of kit as standard, Lexus is selling it for just a few hundred pounds more than the normal RX. And, of course, you’ll easily earn that back with the hybrid’s low fuel consumption.

Or will you? I drove carefully, enjoying the electric silence in town and only rarely putting my foot down hard. And yet it managed only 29mpg. I’ve had more out of that from our diesel Volvo XC90. And on top of this you must factor in the cost of running a hybrid. Think carefully about how much it costs to service a car with one engine, and then wonder how much it will cost to service one that has three.

It’s worth it, of course, if you want your car to make a political statement. “I’m mad and I want you all to know it.” And it’s worth it, too, for sending Ken’s Barmy Army into a tizzy. “It’s a 4x4 and that’s bad. But it’s also a hybrid and that’s good. Aaargh.”

At present I really do think this hybrid idea is just a case of Toyota and Lexus cashing in on the lunacy of the environmental movement. Forcing the Cornish and those right-on American Hollywood types to buy something that is about as green as Charles Kennedy’s hair.

You don’t think so? Well why did they fit all this wondrous technology to a car that has the aerodynamic properties of a small hill.

If they really wanted to make a car that saves the planet it would not only be sleek but also would utilise a few more of the world’s natural resources. It would have, for instance, many solar panels in the roof to keep the batteries charged up for longer, and how’s this for an idea? A wind farm on the bonnet.

No, really, why not stick a dozen mini-windmills out there so that the faster you go the more juice is provided for the electric motors? This would have the added benefit of mincing flies and wasps before they had a chance to make a mess of your windscreen.

You think I’m being silly? Well trust me on this, I’m not being half as silly as the people who’ll buy this car.

VITAL STATISTICS

Model Lexus RX 400h
Engine 3311cc V6 plus electric motors
Power Petrol: 208bhp @ 5600rpm Electric: 165bhp (front) 66bhp (rear)
Torque 212 lb ft @ 4400rpm
Transmission Continuous variable
Fuel 34.9mpg combined
CO2 192g/km
Performance 0-62mph: 7.6sec / 124mph
Price £39,535
Rating 3/5
Verdict Mad as a bag of sandals

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