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Is it a bad idea to use a letter that my former employer wrote for my original application cycle? I feel like I only see people talking about using letters from law school professors when transferring. My employer went to the school that I am applying to. If it is kosher to ask an employer, can I just reuse the letter that she wrote last year, or should I ask her to resubmit one?

Also, is there any issue in asking a visiting prof to write a LOR?