Shortly before the derelict political spoof "First Family" drags itself to a merciful conclusion, ending with a freeze-frame that appears to symbolize rigor mortis, a press secretary played by Richard Benjamin turns to a presidential aide played by Fred Willard and whispers, "I hope we get away with this." Psssst: Not a chance, fellas.

It's difficult to resist the inference that Benjamin is voicing the authentic insecurity of writer-director Buck Henry, who has given himself ample cause to feel fretful and ashamed. Was Henry's co-directing credit on "Heaven Can Wait" an inside joke? A disgraceful solo flight, "First Family" brims with inert camera setups and shabbily lit settings, telltale signs that the director has little pictorial judgment, even with an Oscar-winning cinematographer (Fred Koenekamp of "Patton") on his team.

If verbal humor is supposed to be Henry's strong point, he let himself down with a thud. A typical exchange in "First Family" might find the president's daughter complaining, "I wish Dad were a streetcar conductor," which prompts her mother to the soothing reply, "Of course, you do! Millions and millions of people do!" In quest of really big yucks, Henry reaches back for such corkers as the scene where someone sips a native brew and gets nauseous upon being informed of its ingredients: "donkey blood and cow urine." For this you need a big-shot humorist?

Henry's guiding stale conceit is to portray the occupants of the White House as sitcom jerks. Bob Newhart, becoming a miserable camera subject as his bland features crinkle into middle age, is a paternal dunce called President Manfred Link, a fuming, snappish dad in the worst Danny Thomas tradition. His first lady, Madeline Kahn, is a dowdy tippler, fuzzy-headed and fuzzy-voiced from secret drinking. Their daughter Gloria, Gilda Radner in a textbook one-joke role, is a frustrated, overage adolescent (28 going on 14) who keeps trying to lose her virginity.

The level of humor may be suggested by revealing that Gloria gets her wish in the company of a phallic monolith worshipped by the inhabitants of Upper Gorm, a Newly Emerging African Laughing Stock exploited with contemptible hypocrisy by Henry as the butt of dumb jokes about primitive cultures and the pretext for equally dumb jokes about social and racial squirming on the part of the Links.

The jokes are as heavy as lead from the outset, which shows a TV set tuned to a presidential speech and then a discussion of its inane content while an unidentifiable couple gropes on a water bed in the foreground. The payoff: The president's daughter is one of the gropers, and the Secret Service breaks in to carry her back forcibly to the White House.

The ensuing sequence picks up where this loser left off: The president openly discusses his daughter's randiness with Secret Service agents while presiding at a bill-signing ceremony. On the periphery, Bob Dishy as the vice president begs for a ceremonial fountain pen. For the record, there is one effective sight gag, the first and last of the movie: The president makes a diminutive senator from Rhode Island jump high to fetch his pen. The only other ripple of wit belongs to a brief interlude in which Newhart is seen announcing nuclear disaster in a series of prerecorded spots.

Just as the characters degenerate into one-joke wheezes, the script is predicated on a single flimsy situation. The president is obliged to return a state visit to Darkest Gorm after receiving the ambassador (Julius Harris as a serene savage who speaks English in non sequiturs) in Washington. There's never any reason for the first family to trundle off to Gorm, where crocodiles are roasted on spits, a snake dancer is strangled by her boa constrictor and vegetables grow as big as redwoods (Henry must imagine the Giant Vegetable is a fresh gimmick). For the smirky purposes of this material, it would be sufficient to send the first daughter as goodwill ambassador.

The only apparent aim of "First Family" is to confirm Henry's sense of superiority to people in political life. Fewer humorists may be able to enjoy this luxury if a significant number of paying customers subject themselves to Henry's moldy ridicule.