In the new comedy "Cops and Robbersons," Norman Robberson is the ultimate couch potato, a baby boomer stuck in his youth whose primary obsession is old television cop shows.

In fact, he's knows them so well that given a bit of minutiae about a particular episode of "Baretta," he recites the title, synopsis and even the episode number! He's the only person who has ever rented the Angie Dickinson "Police Woman" tapes from his local video store, and he wears a "Mod Squad" sweat shirt to bed.

Norman says he has always wanted to be a policeman, that he "was born to be a cop."

In truth, however, he dreams of being a TV cop. And he was born to be a boob.

In fact, Norman is the most ridiculous sitcom husband and father to grace the big screen since . . . well, since Clark Griswold, of the "National Lampoon's Vacation" pictures. And since both Norman and Clark are played by Chevy Chase, why not? They're both dumb and clumsy and have dysfunctional families, and they both pretend that everything's OK.

But where the "Vacation" pictures had some satiric bite to offset the silliness — well, the first one did — "Cops and Robbersons" is just stupid. Loaded with ill-timed pratfalls and dopey physical shtick, it's movies like this that give slapstick a bad name.

The story has the Robberson home being invaded by a couple of cops who are assigned to stake out the house next door where a mobster has moved in (and the two "Stakeout" films seem to have provided much of the plot here).

Tough cop Jake Stone (Jack Palance, spoofing every hard-nosed police role he's ever played, and even poking fun at his Oscar ceremony one-armed pushup), along with his young partner Tony (David Barry Gray), moves in with Norman, his stressed-out wife (Dianne Wiest) and their three kids, a snotty teenage daughter (Fay Masterson), an even snottier young son who thinks he's a punk rocker (complete with earring and black leather jacket) and a younger boy who thinks he's Dracula (he sleeps in his toybox and never goes anywhere without his plastic fangs and black cape).

You can guess the rest — but you'll never guess just how amazingly bad it all is. The wildly erratic director Michael Ritchie, whose work ranges from very good ("Downhill Racer," "The Candidate" and the recent HBO satire "The Positively True Adventures of the Alleged Texas Cheerleader-Murdering Mom" — not to mention "Fletch," with Chase) to some that are weak, bad or dreadful ("The Island," "Wildcats," "The Golden Child" — not to mention "Fletch Lives," with Chase) is at his most hamfisted here.

And the older Chase gets, the less appealing his "dumb" act is. He seems to be attempting to encroach on "Ace Ventura" star Jim Carrey's newfound "silly" territory . . . and it's not pretty.

"Cops and Robbersons" is rated PG for violence, nudity, profanity and vulgarity.