I see a lot of people saying that Sarah wouldn't have just gotten in an unmarked police car because she was too professional or savvy or whatever. Aside from being victim blaming, respectfully, none of us (I think) knew her and we can't assume from what we've seen in the media about her background that she would respond a certain way when confronted by an authority figure telling her to do something. Women are raised to be polite and nice and not rock the boat, even if we're independent, successful women so a natural reaction to authority may be to just do what they say or trust them implicitly.