What makes a source more creditble than the other? What questions should you ask when evaluating a source?

Answer 1

If your source is giving you facts on any issue that requires you to keep your source protected, you must verify the facts from at least two different sources aside from the one giving you the information. You must ask your source for names, dates, times,locations etc to do follow up. This requires investigation on your part and you must never reveal your source. Very much like detective work, you must ask people in the vicinity if they noticed anything unusual, or do they remember seeing... You must without a doubt confirm what your source is telling you prior to reporting or confronting.