It shouldn’t be surprising that text that’s repeatedly fed into the LLMs for training is flagged as similar to what comes out of them. The constitution, the bible, and other works commonly spread across the internet are going to likewise be flagged.

Interesting article that goes into some specific detail on what things AI detectors look out for.

Interestingly, after reading the article I was able to get ChatGPT to write an essay that both GPTZero and ChatGPT classified as human-written just by asking it to write with “very high perplexity” (and then with “more perplexity” after the first one failed to pass the test).