Jen Smith, on 17 March 2011 - 21:16, said:
How about legality, DMCA and all that? Sooner or later the MPAA/etc is going after them. I'm not saying good or bad, but I can get the same results from Google as I can "WhateverWarezSite.com" and pick up some torrent or direct download links. Why is one site illegal while another one isn't, even though giving the same results? That sort of thing.
Oh, and +1 for the "I Googled Bing" title, catchy

This is a complicated topic. See the "safe harbour" section of the DMCA. Basically, Google/Bing act in "good faith", taking action on DMCA notices in a timely fashion, therefore they aren't liable for indexing infringing content. Also, they don't target that content specifically, whereas "RandomWarezSite.com" actively pursues that content and promotes copyright infringement.
@OP: For your paper, you should keep the sections on how search engines work extremely light for two reasons. Firstly, since your paper in on ethics, you shouldn't really care about how the technology works, just what it does. Secondly, no matter what you write, chances are you'll be extremely inaccurate. Seemingly simple topics such as following links to crawl are very complex processes.