My first courtroom murder case could have come straight from one of Andrew Taylor’s novels. A gruesome crime — the death of a child. And the murderer was brought to justice by exquisite detective work: police established that the killer had dug a grave but then abandoned it. They also found a witness. That was 20 years ago. The prosecution for cases that I’m involved in now have changed beyond recognition.

Take number-plate-recognition technology. Most murderers drive to their victim, but now cars are tracked by cameras across the country. The police can list vehicles seen near a crime scene, then trace them back. That’s how, in 2006, they caught Steve Wright, the man who killed five prostitutes in Ipswich. I had a case recently where the murderer claimed she hadn’t visited her ex-boyfriend’s house when it was set ablaze. The police gave her car key to BMW, and the company ran some tests. This established what time the car had been started, and the distance it had been driven: the details correlated exactly with the murder.

Or consider the idea of a ‘dirty’ phone, used for nefarious purposes. Criminals think, wrongly, that unless the phone itself ends up with the police, they can get away with their misdeeds. Not any more. Police can look at data and track phones as they move about. If they spot a suspected dirty phone, they can examine its calls, find out when it was used and see if that correlates with the suspect’s known movements. If it’s a match, the jury will hear about it.

Then you have forensic technology, which is advancing at an incredible pace. It’s now very difficult not to leave a trace of DNA at a murder scene. Even if a murderer wears gloves, there’s usually some DNA transfer. I remember a post-office heist in which thieves broke in through the shop next door and stole everything from a caged area. It was a pretty clean job. But they had smoked a couple of cigarettes earlier, and thrown them away at the scene. The police scraped DNA from the butts.

There was also a case last week of a man who killed his wife, then confessed immediately by calling 999. You can see why: going on the run may prolong capture, but not for long. It has never been harder to get away with murder.