I bet his mother kept detailed notes too, and I bet that Kavanaugh has them too. And it is hard to imagine that a judge would even allow her teenaged children to go to drunken unsupervised pool parties.
I would suggest that Brett Kavanaugh’s mother who also happens to be a judge encouraged him to keep a careful diary of all his activities because she would have lived through the disgusting smear campaigns against Judge Bork and Supreme Court Justice Clarence Thomas and would have been very well aware of the importance of her son’s having a bimbo-proof squeaky clean background if he had serious aspirations in the direction of becoming a judge and one day even becoming a Supreme Court Justice.