Partisans, especially Clinton and Trump loyalists, would give you very different answers. And it was Steele, working for Fusion GPS sometime after it hooked up with the Democrats, who compiled the now-famous dossier. The first explanation, as given in various forms by former campaign officials and the DNC, is that they didn't know. Clinton campaign paid for the fake Russia dossier, then lied about it & covered it up." Clinton campaign paid for the fake Russia dossier, then lied about it & covered it up.

Source: CNN October 26, 2017 22:18 UTC