Does the Secret Service check out people who interact with Hillary?

Even Norman Hsu gets a Wall Street Journal head-cut!!! I am at a complete loss of words. Does the U.S. Secret Service actually "protect" Hillary Clinton? Do they check into the people she deals with? How on earth could a convicted felon, FUGITIVE with an active warrant out have such close access to Hillary Clinton (former first lady)? The Wall Street Journal has done an excellent job at chronicling Norman Hsu's misdeeds.
Norman Hsu has been linked to a straw company called Next Components, Ltd. Article from the San Jose Mercury News
From Patrick Healy of the New York Times:

"Clinton campaign aides refused yesterday to release the names of the 260 donors whom Mr. Hsu recruited to the campaign, preferring to wait until they finish their own research on the individuals. Mrs. Clinton and her advisers are concerned that rival campaigns or the news media will dig into the background of each donor, and they want to be prepared if some of the donors end up having money funneled to them from Mr. Hsu or have shady backgrounds."

Norman Hsu's Contributions
A shocking article in the Wall Street Journal talks about where Hsu might have obtained his money. (Hint, it has the same theme of how he got busted bilking investors previously)
To keep up to date on Norman's activities goto NormanHsu.com