There are a number of passages in the Bible -- some more obvious ones being Genesis 3:7-11, Leviticus 18:6-20, and Rev 16:15 -- where having one's secret sins publicly exposed is metaphorically called uncovering one's nakedness. In addition, many rapists rip or cut their victims' clothing to get at the "prize" that much faster, so having their privates so exposed until they can get new clothing is advertising their shame to the world, as in 2 Sam 10:4, 1 Chronicles 19:4, and Isaiah 20:4 (This might also be an alternate interpretation of Leviticus 18.)
It is easy to misread these passages too literally and conclude that physical nudity is shameful in it's own right. The Bible gives us an example of this in 2 Samuel 6, when Michal lights into David for dancing in public in a skimpy undergarment which left nothing to the imagination. On the other hand, many prophets around the time went naked while they were prophesying, so when Michal's father, Saul, in his madness went around naked the joke was that he had become a prophet. In fact, that incident may be a partial reason for her over-reaction.
Altogether, we can assume that nudity in its own right is not necessarily wrong, but we should also take into account the circumstances of any situation, and the sensitivity of the people involved both the principals and the witnesses.
