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I love the math. You could add "no front license plate." Less than half the states use one-plate and most of them are in southern, midwest and eastern states.I plugged into a few different programs, 5 Pieces of evidence in the Kohberger case and the odds of them all occurring and BK being innocent.
Below you can see the odds that this program assigned to each event, which was the most conservative one I used.
Notice how I didn’t mention the DNA.
1. Ownership of the same type of car.
2. Driving at a time consistent with him being the killer.
3. Powering down his phone throughout the murder window.
4. Purchasing the same model knife and sheath, which are now missing.
5. Seeking to purchase the same model knife and sheath, beginning two days following the murders.
Combining the Probabilities
To estimate the odds of innocence, we consider the likelihood that all these events occur together by chance for an innocent person. In probability theory, if events are independent, their joint probability is the product of their individual probabilities. While these events are not entirely independent (e.g., owning a knife and searching for it are related), we can use rough estimates to illustrate the cumulative effect:
Car: ~1/100 (0.01)
Driving at 4 a.m.: ~1/50 (0.02)
Phone powered down: ~1/50 (0.02)
Owning and missing knife: ~1/5,000 (0.0002)
Searching for knife post-murder: ~1/10,000 (0.0001)
If we assume approximate independence for simplicity, the joint probability is:
0.01×0.02×0.02×0.0002×0.0001=8×10−120.01 \times 0.02 \times 0.02 \times 0.0002 \times 0.0001 = 8 \times 10^{-12}0.01 \times 0.02 \times 0.02 \times 0.0002 \times 0.0001 = 8 \times 10^{-12}
This translates to a 1 in 125 billion chance that an innocent person would match all these criteria by coincidence. Even if we adjust for partial dependence (e.g., knife ownership and searching being related), the combined probability remains extraordinarily low, likely on the order of 1 in millions.
And this is the logic (minus the math) that got me, and I imagine many others, to conclude that law enforcement arrested the right person. Then add the DNA. Add the issues with women. And then let's see what forensics turned up in that apartment.