by Abi Silver
‘Both verbal and visual, so we heard a clear verbal direction – “please resume control of the vehicle” – and a red light will usually flash on the dashboard with the words “resume control”.’
‘What happened then?’
‘Mr Salisbury did not reduce his speed until he was almost level with the traffic light itself. I conclude in my report that he didn’t see it, till very late. Mrs Layton has said he was looking at his mobile phone, so that may be why. He passed straight through the traffic light, which was at green, and as he did so, he moved out of his lane. He swerved suddenly to the right, into the southbound carriageway, then to the left, bringing him back into the northbound carriageway and, ultimately, into a collision with the family, who were in the process of crossing the road.’
‘In your opinion, was James Salisbury in control of the vehicle at the moment of impact?’
‘Yes, definitely. The data also shows that Mr Salisbury applied the brake, and that the car was braking rapidly and speed was reducing in accordance with expected parameters. I found no evidence of any problems with the braking or steering systems, which remained intact after the accident.’
‘And there is no doubt, in your mind, that the car responded to Mr Salisbury. By that I mean, when he steered it right, it travelled to the right and when he pulled the wheel to the left, the car followed?’
‘No doubt at all.’
‘Thank you, no further questions.’
***
‘Hello Mr Abrams. Can I clarify for my benefit and everyone else here, what your area of expertise is please,’ Judith was brisk as she tried to re-take the initiative.
‘Certainly. I am a forensic crash examiner and I also advise the Department of Transport on road safety issues. I have fifteen years’ experience visiting and advising on crash scenes, including analysing and understanding technical faults in vehicles and identifying road hazards. I have also undertaken specialist training on the impact of new technology in this area, working closely with car manufacturers. Every time more sophisticated systems are brought in, like advanced steering or assisted braking, it impacts how cars perform, and I need to keep up to date with that, to be able to do my job.’
‘So artificial intelligence is not your thing?’
‘No. Thank you for highlighting that. I am not a computer scientist or AI specialist. However, I do know a lot about autonomous vehicles because I keep myself up to date with all the related technological advances. But I don’t, for example, have experience myself of computer programming or the technical side of how the computer systems which run these cars operate.’
‘Thank you. Now I want to delve below the surface a little, so that I can really understand what you were telling the court just now.’
‘Be my guest,’ Mr Abrams replied.
‘You talked earlier about Mr Salisbury holding the steering wheel. How do you know that?’
‘The data records pressure being applied by his hands to the steering wheel.’
‘But does that mean he was holding the wheel?’
‘What do you mean?’
‘You say that you can detect now that pressure was applied but is it possible to distinguish between gripping the wheel with your fingers and, say, resting your elbows on the wheel, which a person might do, sitting in the driver’s seat, reading a book or, as you have mentioned, scrolling through messages on a phone.’
‘It isn’t possible to be that precise, no, but there was contact which was more than transient between Mr Salisbury and the steering wheel.’
‘Ah. So the data doesn’t really illustrate pressure in the sense of someone squeezing the wheel, but simply contact, in that part of Mr Salisbury’s body was touching the steering wheel over a period of time?’
‘Continuous period of time and in the same place and at the traditional ten-to-two position, which is why I concluded he was holding the wheel, but, yes, we don’t have data on the strength of grip.’
‘And also, just to clarify, your data shows us that Mr Salisbury also applied pressure to the manual mode button at somewhere between 150 metres and 70 metres from the collision site, but do we know how much pressure?’
‘No.’
‘Or if it was sufficient to operate the button? It’s like buttons on a lift or on a keyboard, some require more pressure than others in order to be operative.’
‘He pressed the button. We can’t say precisely how hard.’
‘And there is no way of showing that the car was in manual mode?’
‘I don’t understand the question.’
‘What I mean is, there is no big flag on your data which says “this car is now driving in manual mode”. You glean that information from reviewing the other data, so, for example, on a continuous stretch of road, you would know the car was in autonomous mode because it would be accelerating and decelerating without any pressure on the pedals. Is that correct?’
‘Precisely.’
‘So you have drawn the conclusion that the car was in manual mode, because Mr Salisbury pressed the button, you can’t say how hard, and then, what? Applied some pressure to the brakes?’
‘Yes. And held the steering wheel.’
‘Yes. Thank you for reminding me of that. What happens if a person presses the brake, when the car is driving autonomously?’
‘Nothing.’
‘So, if, for example, I was in one of these vehicles and I mistakenly leant my foot on the brake, the car would ignore me. And if we were to examine the data afterwards, we would see, what?’
‘We would see you applying pressure to the brake but the car not slowing down, so we would know the car was in autonomous mode.’
‘Or it could be in manual mode, but the brakes have failed?’
‘In theory, yes, but I checked the brakes on this car and they were operating correctly.’
‘But that was after the event.’
‘Yes.’
‘So, just so I am clear, the only evidence you have of Mr Salisbury being in control of the vehicle is what appear now to be desperate attempts by him to brake and steer the car away from danger, recorded by sensors on the steering wheel and the brake pedal. How were these recorded?’
‘They were recorded by the EDR, the event data recorder.’
‘Let’s say, hypothetically, Mr Salisbury had never pressed that button. Is it plausible that, in the seconds leading up to the crash, he still might have grabbed the wheel and pumped the brake, in a normal human response to an impending collision? It would look as if he was doing the work, but the car remained in control?’
‘But the sensor recorded that he did press the button.’
‘All right. Talking about sensors, can you tell us where the sensors on the car are situated?’
‘The round structure on the roof is the main navigation system. It’s called a LIDAR, as it combines laser and radar technology. Then there is a sensor on the driver’s side front wheel which can accurately pinpoint where the car is on a map. There are video cameras on the dashboard which help the on-board computer system detect moving things, like pedestrians and other cars. And, finally, there are four radar sensors, three in the front bumper and one in the rear, to help guide the car.’
‘Can I take you, for a moment, to a still image of the vehicle? Thank you. Now you’ve shown us that the bumper on the driver’s side was damaged, quite substantially. What had happened to that radar sensor, in the bumper?’
‘It was crushed.’
‘You don’t mention that in your report?’
‘Maybe not.’
‘Is it possible to tell, from the data you reviewed, whether that particular front sensor was operating properly before the crash?’
‘No. It isn’t.’
‘How might a sensor like that, set into the bumper, become damaged?’
‘They are qui
te fragile. A knock into another vehicle would damage them.’
‘Or even coming too close to a low wall, like in the car park my client had used, immediately before this journey?’
‘It’s possible, yes. But I would expect a signal to be sent if any sensor was out of action.’
‘Did you check for any signal?’
‘It would be a contemporaneous message on the dashboard so it’s not possible to check now.’
‘So how did you reach the conclusion that the sensors were operating properly?’
‘All the other sensors were intact after the crash.’
‘Apart from this one, the one closest to Mrs Layton?’
‘Yes. I accept that it’s not possible now to ascertain if that sensor was operating properly before the crash, because of the damage it sustained.’
‘Thank you. Why did the car not slow down when it approached the temporary traffic light sign?’
‘I don’t know.’
‘If the car was mimicking the actions of a human driver, we see a temporary traffic light sign, and a sign telling us to “slow down” and we do. Yet this car didn’t do that. Instead, you say that the EDR shows that it sent an emergency request to the driver to re-take control, and continued on its existing trajectory, at its existing speed. I am asking you why that happened?’
‘And I am telling you I don’t know. I can tell you if certain components were working and were utilised, but I can’t tell you why. I can’t get inside the head of the car’s control system. It’s very difficult to explain after the event why such a complex piece of software has made a decision. It’s like asking what, precisely, goes on inside a human brain to instruct a human to perform an action.’
There was silence in the court as Mr Abrams’ words sank in. Mr Abrams was accepting, without any qualms, that he did not have the answer, that all he could do was suggest plausible explanations for what might have happened inside the computer, and that was unlikely to satisfy the Laytons or the public. The key question for James, of course, was the impact on the jury. Judith stole a snatched glance to see if Constance was making notes, but Constance was disappearing out of the back of the court, in a hurry.
‘But, like I said at the beginning, it’s not my field,’ Mr Abrams continued. ‘If you want to know why things happened, you should get one of the SEDA technicians in. He’d be able to tell you if I’m right or not.’
‘Thank you. We may just do that.’ Judith made a play of looking across at the clock.
‘Your honour. I am noticing the time, and I still have quite a way to go with this witness. But I was about to move on to another topic.’
Judge Wilson checked the time too and closed his notebook.
‘Very well. We’ll stop there. Back at 9am tomorrow please.’
***
Constance had just completed a hurried phone call in the waiting area outside the court and was making notes on her iPad, when she heard a familiar voice.
‘Hi, Sis.’
She turned around and Jermain was standing before her. She gasped and then she smiled.
‘How did you know I was here?’ she said.
‘I asked at your work.’
‘You know where I work?’
He pointed to his phone. ‘I looked you up. It says so many good things about you, I thought they must have got the wrong person.’
‘Thanks.’
He opened his arms and she went to him. It was funny how it was always that way around. She was the big sister, but he always gave out the hugs.
‘You didn’t say you were coming,’ she said. ‘I’m in the middle of a trial.’
‘They said. But I was just delivering something up the road and I saw how close I was.’
‘Delivering? Is that part of your new job?’
Jermain withdrew. ‘You ask so many questions. You always do this.’
‘I’m sorry. I was…interested.’ Constance examined his face, clean-shaven, his hair cut shorter than before. ‘How long are you in London? Can I, at least, ask that one?’ Jermain looked past Constance as someone exited the court and the low murmur of the proceedings spilled out.
‘Nah. This is it,’ he said. ‘I’m passing through. It’s lucky you were here and not inside. You got cross with me that time I waved. Remember? I have to go. In fact, I might have a parking ticket by now. But I just throw ’em away.’
Constance opened her mouth to protest.
‘Only joking,’ he said.
Constance thumped his arm.
‘Come and see me properly soon,’ she said, ‘for a bit longer!’
‘Sure.’
He was already walking away.
‘You can pick up your post.’
He had gone. Constance ran to the door of the building, but she couldn’t see him anywhere. He had been swallowed up by the crowds and disappeared.
***
Constance joined Judith as she exited court, and they huddled together in a quiet alcove while the other lawyers and the public filed out.
‘Where’ve you been?’ Judith asked.
‘I just wanted to make a quick call, on that point Abrams raised about why the computer does things, for your cross-examination. Greg says “hi” by the way.’
‘Why have you been speaking to Greg?’ Judith’s tone was sharper than usual.
‘I thought he’d know the answer,’ Constance said. ‘And he did. Something he said when we all had dinner together. You’ll definitely want to use it on Abrams tomorrow.’
‘All right,’ Judith mumbled her agreement. ‘And the traffic light?’ she asked.
‘It’s taken this long for me to find the contractor’s name. I’ll try them again now, but it may have to wait till the morning. How do you think it’s gone with Abrams?’
‘Fine, I think, but I’m fed up fighting with one hand behind my back. I mean, “damaged sensor”. I used it, but is that seriously the best James can do? I’m wondering if we should introduce the hint of someone tampering with the car. Do we have anything at all we can use to support that?’
‘Nothing. You’ve seen Abrams’ report on the car itself. And I spoke to the security guy a few weeks back and he said he’d never seen anyone near the car. I also caught up with the gardener, who said the same.’
‘Was there any reason for either of them to lie?’
‘I can’t think of any. They both seemed genuine, although Leo, the gardener, hinted that there was something going on between Martine and the security guy, Dean.’
‘Did he?’
‘He asked if James might go to prison and when I said I hoped not, but it was possible, he said he thought Dean might enjoy the prospect of free access to Martine.’
‘Free access?’
‘Those weren’t the words he used, but that was the gist.’
‘And you didn’t think it important to tell me this before?’ Judith pulled off her wig and attempted to straighten her hair.
‘I met Dean. He seemed straightforward. I couldn’t see it happening. I thought maybe Leo was making trouble.’
‘All right. Like you say, we have no evidence of the car failing, so it’s probably irrelevant for today’s purposes, even if Dean has been dipping his toe in James’ pond. I was on my way to see James, anyway, to insist he provides more help. Otherwise I’m in danger of drowning out there.’
‘Are you going to tell him that?’
‘I am. Not that it will do any good.’ Judith sighed. ‘Martine says “he’s stubborn”, as if that makes it all right. And that he feels morally responsible. As if we didn’t have enough to contend with. Come on. I could do with some back-up. I’ll be bad cop,’ she said, ‘just in case you were wondering.’
***
James was sitting, hands clasped together, staring at the floor, when Judith and Constance entered.
Judith began to walk forward, then checked her own progress and sat down, taking out her notebook and pen.
‘In case you wanted to know, everything today was as expected. Nothing we can’t deal with,’ she began.
‘Thank you.’ James spoke to the floor.
‘But the things I talked to the witnesses about, the sensor, whether you were holding the steering wheel, they’re hardly revelatory. Have you really told us all you can?’
James sat in silence. Judith flicked through her notes again and Constance took advantage of the hiatus to approach James herself.
‘This is a difficult case, I know,’ Constance said. ‘And the lives of one family have been changed forever. And it’s rubbish. I know that. And you probably feel you can’t walk along the street and look people in the eye because they all think it was your fault. That you need to endure some kind of punishment to redress the balance. But you have a family, too. You have a wife and two sons. If we don’t do enough to raise the doubt that you were responsible, then you will go to prison. How will that be for Martine? How will that be for your children?’
‘You’re not really making things better. Do you know that?’ James looked up for the first time.
‘Well I am sorry for that!’ Constance’s voice was gradually increasing in volume. ‘But some things have to be said. Judith and I are fighting to defend you, but it’s like climbing a mountain in a…a pair of slippers. Are you really going to stand up in court and say that you “must have been” driving in manual mode, even though you don’t remember what happened? That’s just opting out, and the jury will see that too.’
Constance was unstoppable in full flow.
‘You think that sounds better than putting your hands up and saying, “I’m guilty. I wasn’t looking where I was going. I killed those kids.” Well it’s not better, it’s worse,’ she said. ‘It’s accepting you killed them, but you don’t even have the courage to admit it. Is that really what you want your legacy to be? After all your years of hard work?’
‘Leave me!’ James leapt to his feet, his voice reverberating around the tiny room and Constance sprang backwards.
Judith rose and collected her things. She took Constance’s arm and led her towards the door.
