No one wants to be a SNITCH. Doesn't look good on a resume. But where do YOU draw the line between keeping confidences and disclosing them?

When it becomes a danger to others.

Fortunately, I haven't been in a position where I've had to put anything on the line by deciding whether to snitch or not.  I would like to think that if the issue was a matter of danger to others, I would do the right thing and bring the issue to light.

  "No one wants to be a SNITCH."

  Hmmm, what a premise. Assign an apparently negative connotation to something, then invite people to decide whether or not they want to be identified by it. Here's a different perspective on the theme you've introduced: instead of the label "snitch", I dare say that there are plenty of people who speak up when they are aware that a crime or infraction has been committed, when they have information that could be helpful to the authorities. By saddling those people with the pejorative term "snitch", or by referring to the process with the negative assignation "snitching" presupposes that the correct thing to do is to assist, aid, harbor or abet nefarious persons in the commission of their acts.  
  Were you to ever become the victim of a violent crime or the loved one, the survivor of a victim, and a third party had information that would shed light on the facts, I doubt you would advocate the withholding of that information just so the third party could avoid being considered a snitch.
  So, in summary, there may be many people who do not want to snitch, to be thought of as snitches, etc, and for those reasons might remain silent when their voices would potentially assist a victim. There are others who would do what is right and alert the proper parties as to whatever knowledge they have to help out. I do not think that they are snitches, nor that they are snitching. 

when you need to disclose them