The wicked man mentioned here is one who is guilty of doing a wrong - thus a criminal or a transgressor. This is a man who has sinned against others in what he has done. We are told in this proverb that when this kind of man comes - contempt also comes. The contempt mentoined here is an attitude of disrespect and scron towards him. Thus when the wicked man comes around there is also disrespect and scorn. There is something about someone who breaks the law - who disregards what is right - that brings about a response of scorn and disgust. Look at the recent events surrounding Tiger Woods. He was viewed as a man of great integrity and honor until it became known that he was having multiple affairs. Suddenly all the respect turned to scorn. This is how a wicked man - a law breaker is received.
The rest of the proverb tells us that with dishonor comes scorn. Dishonor here refers to something disgraceful and full of shame. When this kind of thing comes, then scorn comes as well. This word means a reproach, a taunting - usually hurled at an enemy or someone who is ungodly. The wicked may be able to hide many of their actions for a time - but eventually things will come to light. When they do - then comes the contempt, the shame, the disgrace, and the scorn and reproach. It is better to walk with the Lord and keep to His paths and ways - than to face the reward of the wicked - contempt and scorn.