Here is my policy, in brief, on graduate school references, because every year, I get a ton of requests for them - sometimes twenty or more, in the past. Even though they are largely webforms now, they still take time to prepare. Here are my policies:

Note: if I have previously caught you in an act of academic dishonesty (a violation of academic integrity), I will not provide a reference for you for any reason whatsoever. I cannot recommend anyone who cheats to gain an undeserved position.