The New York Times appears to blow up the pitch-tipping allegations against Alex Rodriguez:
If a tipping conspiracy were in place, one would expect that Rodriguez and rival middle infielders in games he played to have hit better in low-leverage situations than in high-leverage ones. Using a fairly loose definition of high leverage as a L.I. above 1.5 and low leverage as below 0.7, the data provide a resounding answer: either no tipping was going on or it was pathetically ineffective.
Contrary to his reputation as a choker, Rodriguez was actually at his best when the game was on the line as a Ranger. According to data compiled by Sean Forman of Baseball-Reference.com, his combined on-base and slugging percentages (O.P.S.) from 2001 to 2003 was 1.076 in high-leverage situations, compared with 1.017 for medium leverage and .982 in low leverage. Opposing second basemen and shortstops showed the same pattern. They registered an .899 O.P.S. when leverage was high, .825 when it was middling, and .817 when it was low. Unless Rodriguez's behavior was even more nefarious — tipping only when it mattered most — the numbers give no reason to believe he was involved.
I don't doubt that someone, somewhere told Selena Roberts that Rodriguez was tipping pitches. She had a duty, however, to go further than to simply reprint such an allegation without anything further. At least she did if she wanted to do anything other than be a gossip monger. But in this case her journalistic curiosity—to the extent she still has some—was easily trumped by the fact that she really, really wanted to believe the worst about Alex Rodriguez, and whatever she was being told fit the bill.
The "this is too good to check" vibe comes through many times in that book. For example, in the book, some anonymous source says Rodriguez "may" have used steroids in high school. And he may have. But instead of resting on a single allegation -- which Roberts did -- why didn't she get a comment from Doug Mientkiewicz, Rodriguez's high school teammate and friend, and a person whom she already quoted about other topics? Mientkiewicz said a couple of weeks ago that the allegations of Rodriguez's steroid use in high school were implausible. Did Roberts ask him when she was researching the book and didn't like the answer, or did she not ask at all because she didn't want to know the answer?
At any rate, both of these examples show that you can write a hatchet job without technically lying about your subject. You simply have to have the desire to run whatever gossip you hear and combine it with a disinclination to dig any further.