Before Slater wrote The 57 Bus, she wrote a long-form article on the case for The New York Times Magazine, in which she gives a more "broad strokes" version of the case and the trial. In many ways, the article is a microcosm of the full-length book. She offers alternating perspectives, starting with Sasha's background and working her way to Richard's. She shows how their threads intersect on that fateful day on the 57 bus, when Richard and some friends decide to "play a prank" on a sleeping passenger by lighting their skirt on fire. Slater portrays Oakland as a city of both diversity and disparity. Some passages are lifted verbatim from the article and dropped into the book. However, the article and the book differ in some critical ways other than mere length, and those differences come down to the perspective.
A notable difference in the article is Slater's use of the first person, which is never used in the book. In the article, she writes, "Oakland is a city of more than 400,000 people, but it can often feel like a small town. The attack happened in my neighborhood, on a bus my own teenager sometimes takes home from school. Sasha Fleischman’s family and my family have close friends in common. Richard Thomas once attended my son’s high school. But even when events unfold practically on your doorstep, it isn’t always easy to make sense of them.". If you've read the book, some of that passage might sound familiar. Slater opens the section "OAKLAND, CALIFORNIA" with the first sentence quoted above. But Slater, as a person, is totally absent from the book. By resisting the first person entirely, she makes her role as author invisible and lets the story breathe on its own. Even in the more experimental, lyrical sections of the book, Slater tends to rely on primary sources from the perspectives of her subjects. In the section "TUMBLING," Slater adapts posts from Sasha's Tumblr into a free-verse poem. The length and freedom that comes from writing a full-length book allow Slater to step aside and let the story do 100% of the talking.
Another limitation of the article is the form and the limitations of the publication itself. At one point, Slater writes that "telling Sasha’s story also poses a linguistic challenge, because English doesn’t offer a ready-made way to talk about people who identify as neither male nor female. Sasha prefers “they,” “it” or the gender-neutral pronoun “xe.” The New York Times does not use these terms to refer to individuals" (Slater). In other words, because her article is being published by The New York Times, Slater is required to follow their linguistic standards, lest her story not be published at all. But as a compassionate person, Slater has an obligation to her subject to represent them in a way that they are comfortable. So, if you read the article, you'll notice that Slater refers to Sasha by their name quite often, because she isn't allowed to use "they" as a pronoun to refer to a single person by NYT standards.
Clearly, when Slater was approached by Farrar, Straus, and Giroux to write this story in a full-length, Young-Adult, investigative format, she was given more freedom to write it the way she felt was most communicative of the case and most respectful to all involved.