I’m watching Dateline and this suspect left a police interview and committed another murder. The first cops couldn’t arrest him because their evidence was all circumstantial. While they are looking for him now, the voiceover says DNA results are still not back. At this point it’s been several weeks. So Eli5 – DNA results: wtf takes so long?
Is there only one machine in the world? Can’t they move murder cases to the front of the line? Does the DNA fairy only come once a month? Does DNA take 500 hours to marinate? Can the cops buy another DNA machine? Do we need a GoFundMe?
In: 6
Tldr; first part is that analysis takes time, even if pushed to the top of the queue. And tests need repeated to be confirmed and validated.
Second section I wrote is on dna evidence can also be circumstantial evidence. Most evidence in cases are circumstantial evidence. You just need to have overwhelming amounts of circumstantial evidence that all point to guilt to be beyond reasonable doubt.
Violent crimes and murders will take priority, but there are still thousands and thousands of samples. With the best tech, the sequencing is fast (but let’s face it, the police do not get the most uptodate machine bought for them every time a new one is brought out). However, the analysis of that sequencing info is what takes time. To say one bit of dna belongs to that person you need to compare multiple areas within the dna. You then need to repeat the tests to confirm the findings.
On top of this, just because you have dna match, it doesn’t mean that is not circumstantial evidence. And a lawyer can argue that. Depending on the case it could be explained away in different ways.
The World’s End murders in scotland happened in 1977. It was a cold case for decades and someone was tried in 2007 based on dna evidence found. The accused, Angus Sinclair claimed he’d had consensual sex with the victims and that any harm that came to them, happened after. So the dna was circumstantial evidence. He was acquitted
This was the case that got Double Jeopardy laws in Scotland over turned, and the first case to be retried. Sinclair was retried in 2014 further forensic evidence had been discovered (had not been looked for previously as the prosecutors thought the dna was enough evidence, but that’s a whole other issue). He was convicted then and sentences to life. Dies in prison in 2019.
Most cases use circumstantial evidence, it’s just when you have more and more pieces of evidence adding up that you can prosecute. Fingerprints at the scene, could be there because the suspect did it, or were there before the crime occurred. Fingerprints on the weapon; defence are not disputing that the weapon belongs to the suspect, just that someone else used it for the murder. Semen present, consensual sex. Video evidence showing the suspect in the area at time of the crime, doesn’t mean they did the crime. But add them plus other things up, is how you get the case.
So I’m your case, they were waiting for a further bit of circumstantial evidence. Probably would have been enough to have him off the streets, but it doesn’t mean that there weren’t other things that could be looked for either.
Latest Answers