In our present system of justice, he rearely can. I think the only way to assure that a confession is true and voluntary is to have counsel present. Maybe you could say that gossiping is passing on other people's confessions. They both respond to our desire to know more about the inner being of other people. And thus it's no accident that both confessions and gossip have a lot to do with the novel.
Novels are often confessional in form, and they often purvey gossip.
I just want to point out that Court TV Online will soon be presenting a special section devoted to confessions, including several video confessions, like Brandon Wilson re-enacting the murder he committed for police. The book is a meditation on the strangeness of the fact and act of confession. Also, with psychoanalysis as a modern secular form of confession. And to some extent with the history of the religious practice of confession, and its enormous influence. And then I reread a number of works of literature.