If you are asking people to write you letters of recommendation, my advice is to make every effort to read these letters before they go out to their intended recipients. If you need to cheat, lie, and commit minor criminal acts to get access to those letters, consider doing it. Because letters of recommendation are often mean as hell. I don't know whether it's true that one isn't allowed by law to write a negative letter of recommendation. I do know, however, that most people are smart enough to write a letter that seems to be nice on the surface but ends up hurting the candidate's chances of employment severely. Here are a few examples from the letters of recommendation I have seen with my own eyes. I have changed some factual details in them, but the nasty digs at the candidates have been preserved in their entirety.
- "You might have heard about the numerous conflicts this candidate has had at her previous places of employment. You don't need to believe all of these accounts of strife, however." - No, we never heard anything like that about this candidate but I guess we have now. Thanks to you, kind colleague.
- "The only thing I can tell you about this candidate is that he is a really nice guy." The only thing?? So he isn't a great pedagogue, an important scholar, a talented administrator? He is just a nice guy? And we are supposed to pay him 100K per year for being a nice guy?
- "I am happy to recommend Professor X for the position of Full Professor of German. His command of German is quite good." "His Spanish is quite good" is what I say about my B- undergrads. Is it possible that the recommender honestly doesn't know that a Full Professor of German is kind of expected to be better than "quite good"?
- "This candidate is often disliked by his colleagues. Some people might refer to him as stubborn and conflictive. I, however, have never had a slightest problem with him." Right. And that slight problem that you never had with him is now making you characterize this candidate in a way that will make him unhireable everywhere in the world.
- "All I can say about this candidate is that if you need to discuss anything trivial - like where to do the laundry, or where to take your kids during summer holidays - he is the person for you." Of course, if this were a position in Trivial Studies we might be interested. But offering a Full Professorship with tenure to someone whose main contribution will be to discuss the best place to do the laundry might be a little hard to sell to our Dean.
So once again: be very very careful about whom you ask to write your letters of recommendation.