The pervasive influence of corporate cash in the democratic process, and the extraordinary lengths to which politicians, lobbyists and even judges go to solicit money, are laid bare in sealed court documents leaked to the Guardian. The John Doe files amount to 1,500 pages of largely unseen material gathered in evidence by prosecutors investigating alleged irregularities in political fundraising. Last year the Wisconsin supreme court ordered that all the documents should be destroyed, though a set survived that has now been obtained by the news organisation. The files open a window on a world that is very rarely glimpsed by the public, in which millions of dollars are secretly donated by major corporations and super-wealthy individuals to third-party groups in an attempt to sway elections. Five Wisconsin prosecutors carried out a deep investigation into what they suspected were criminal campaign-finance violations by the campaign committee of Scott Walker, Wisconsin governor. In 2015, Justice Prosser refused to recuse himself from a case in which the state supreme court sat in judgment over the John Doe investigation, despite the fact that the investigation focused on precisely the same network of lobbying groups and donors that had helped him hang onto his seat. The judge joined a majority of four conservative justices who voted to terminate the investigation and destroy all the documents now leaked to the Guardian.