DNA Is Everywhere — So Why Was Trace DNA on Daniel’s Fly Treated Like a Smoking Gun?

If you follow Daniel's case, you’ve probably heard prosecutors repeat one line over and over: “There was DNA on the fly of his pants.” The implication is always the same: DNA equals guilt. Case closed.

But that’s not how DNA works.

A 2023 forensic study in the Australian Journal of Forensic Science on brand-new, unworn underwear drives this home better than any argument could. Researchers wanted to know what DNA is already sitting on underwear straight out of the package. The answer is almost unbelievable unless you understand how messy the real world is.

Here's what they found:

1. Most brand-new underwear already has someone else’s DNA on it.

The researchers tested 24 pairs of new, unwashed underwear. Male DNA showed up on 17 of them — even though the study used only female handlers.

Let that sink in. No men touched these items. Nobody wore them. Yet they still had male DNA on them.

Why? Because underwear passes through a whole chain of people: factory workers, warehouse staff, packers. Every step is a chance for DNA to land on the fabric.

Underwear is basically a sponge for stray DNA.

2. Just 30 seconds of brief handling left enough DNA to detect.

One of the study’s goals was to see whether a quick touch could leave measurable DNA. It did.

If 30 seconds of touching unworn underwear leaves trace DNA, imagine what happens to pants someone wears on duty all day.

3. Most of the DNA amounts were extremely small.

Most samples had only tiny amounts of DNA, yet the study was still able to pick up random, stray contributors. This is the kind of trace-level material found on Daniel's fly: minimal, mixed, and scientifically weak. But prosecutors treated it like it was a clean, definitive fingerprint.

What this means for Daniel's case:

Prosecutors argued that trace DNA on the inside and outside of Daniel's fly meant vaginal DNA from a specific accuser was deposited during a sexual assault.

But this study shows:

• DNA doesn’t prove sexual contact. Most low-level DNA is just shed skin cells.

• DNA on clothing is very easy to transfer. Even brand-new underwear picks up multiple

  contributors.

• DNA mixtures are routine, not incriminating. The study shows they happen without anyone ever wearing the item.

Trace amounts are basically forensic background noise. Treating them as proof of sexual assault is a misuse of the science.

When DNA is everywhere, the presence of microscopic, low-level samples isn’t evidence of guilt. It’s evidence of how messy, unpredictable, and easily transferred DNA really is.