Clark and Maxa are the two Washington Post reporters who broke the seamy tale of Congressman Wayne Hays and Liz Ray, the dumb blond with calendar-girl dreams. A very tacky story it proved to be; before they put it on paper, Clark and Maxa eavesdropped on Hays' smutty phone calls to Liz and trailed the pair in a ""gumshoe chase"" that's the stuff of grade-B movies. To rise above their lowlife subjects, Clark and Maxa expound on Congressional fringe benefits--freebies that range from fancy dinners to lavish travel junkets and payrolls padded with ladies of doubtful virtue. They also insert frequent reminders that the bills for these delightful privileges are being footed by the taxpayer. Hays, the powerful chairman of the House Administration Committee and by all accounts a rare s.o.b., makes a perfect object lesson in the daily abuse of power that goes on in Congressional fiefdoms, where each office is staffed by aides whose prime duty is ""glorification of the man."" All these unscrutinized bonbons produce hubris, chide the authors, and--as in the Nixon White House--a dangerous isolation from ordinary folk who are not part of the club. Since the fallout from the Hays' scandal was plentiful and further unsavory disclosures seem certain, this may draw an audience that extends beyond those who dote on the sinful doings of Washington potentates. But it's doubtful whether most people will be shocked--or even surprised.