IN POLITICS these days, no life goes unexamined. Reporters ask about medical history, tax returns, drinking habits, visits to psychiatrists, relatives, grade-school marks, plagiarisms and any teenage hi-jinks such as shooting up mailboxes in Wyoming. Candidates know surprises can be fatal to a political campaign.

So meet a new breed of private investigator -- or let's say political "security consultant" as author Jerome Doolittle does in Body Scissors (Pocket Books, $17.95). It's a riveting political thriller written with an insider's savvy by an author who has been a Washington newspaperman, Carter speechwriter, and U.S. embassy spokesman in Laos. At the same time that he skewers the practitioners of political skulduggery, Doolittle also has written a well-clued mystery that moves smartly to a jolting resolution.

Tom Bethany is asked to do a routine background check on J. Alden Kellicott, a professor at the John F. Kennedy School of Government. A Democratic presidential candidate plans to announce that Kellicott will be his choice for secretary of state if he is elected. His campaign manager wants somebody from the outside to do the "woodshedding" to avoid, as he puts it, the risk of another Eagleton or Ferraro.

As any good researcher, reporter, or investigator would do, Bethany first follows the paper trail through newspaper clips, transcripts of congressional hearings when Kellicott was a State Department official, and standard reference books. Only two anomalies break the pattern of a successful man who has led a circumspect life: no mention of Kellicott's parents in his entry in "Who's Who" and the murder of his older daughter two years earlier.

As for Kellicott himself, a man couldn't be more cooperative when Bethany asks for access to his doctor, accountant, teachers and family. And it is Kellicott himself who first mentions his daughter Emily's murder, speaking in sorrow of a troubled young woman who dropped out of Wellesley in her freshman year, became a druggie and a topless dancer, and was found naked and strangled in a snow pile on a parking lot.

Bethany digs deeper, talking to Kellicott's old schoolmaster and former aides in the State Department. He tries to piece together Emily's life before her murder. His investigation leaves some disquieting questions: Why do Kellicott's former teachers and aides distrust him, yet praise his abilities so highly? What was the respected college professor doing outside a porn shop in Boston's Combat Zone? Was he there to rescue his daughter as he says? And why did Emily, who turns out to have been a talented artist with a sketchbook of Combat Zone portraits in her purse, tell friends that her father died when she was 13?

As Bethany keeps asking questions, there is an attempt on his life, which he thwarts with his skills as an Olympic-class wrestler (he never will forgive President Carter for the U.S. boycott of the 1980 Olympics, which cost him the chance to win a medal). What began as a routine background check ends with the revelation of an unspeakable crime, followed by gruesome justice meted out in a sauna bath.

Doolittle offers a polished performance in his first mystery. The Boston scene is a lively backdrop, the dialogue crackles with fast repartee, and the characters make an assorted and colorful cast ranging from Boston brahmins and politicians to massage-parlor operators and pimps.

This praise must be tempered. Attentive readers will pick up the drift of the plot halfway through Body Scissors. Still, there is enough narrative energy and suspense to carry to the end.

And, then, there is Tom Bethany himself, so clever and witty as the narrator with his caustic, biting cynicism. At first, it's quite entertaining but later begins to wear thin. Cleverness can backfire if it is pursued too relentlessly.Carlotta's Capers THERE IS something special about redheads. At least that is true for Carlotta Carlyle, the 6-foot-1-inch private eye who moonlights as a Boston cabbie to pay the real estate taxes on the rambling Victorian she inherited -- along with a parakeet named Red Emma -- from an aunt.

In two previous outings (The Snake Tattoo and A Trouble of Fools), Carlotta established herself as a worthy competitor in the private-eye business. Now, in Coyote (Delacorte, $18.95), Linda Barnes does not fail her spirited heroine, devising a case that takes Carlotta into the dangerous, shadowy world of illegal aliens and the "coyotes" who exploit them.

A Hispanic woman who calls herself Manuela Estaban asks Carlotta to retrieve her green card -- the prized credential that allows an alien to work legally in the U.S. The card is in police custody since it had been found on the corpse of a dead woman three weeks earlier. Carlotta's visitor knows only a few words of English. What she does communicate is her paralyzing fear. She flees before Carlotta can pin down her address.

Carlotta suspects that the Hispanic woman's visit may be linked to Paolina, her 10-year-old "little sister," but she runs into a stonewall of silence when she questions the girl and Marta, the harried single mother who is trying despite her painful arthritis to raise a family alone.

One of the best things about this series is the sensitively handled relationship between "Big Sister" Carlotta and Paolina, whose overworked mother is too pressed to reach out with love and affection. It is a relationship that is as important to Carlotta as to Paolina.

Before the "coyote" who preys on illegal aliens is trapped, three more Hispanic immigrants -- including Carlotta's visitor -- are brutally murdered. Then the murder takes Paolina hostage as Carlotta and the police corner him in a crowded Boston subway station.

Carlotta is an engaging narrator with a brisk, easygoing style. She is bluntly candid about her relationship with the men in her life. There is Mooney, her former boss when she was a police officer, who would like to be more than a friend. But, as Carlotta puts it, "the wild and crazy chemistry is not there." That comes with Sam Gianelli, the son of a Mafia boss, who may have been too long absent in Italy when Carlotta meets a handsome immigration agent. By the end of Coyote, she has gotten a chemistry lesson. The Deckers Are Dying NO ONE IN THE mystery field is more delightful than Barbara Paul, who has a talent for coming up with diabolically clever plots and quirky characters. She has done it again in In-laws and Outlaws (Scribners, $17.95).

Gillian Clifford Decker, who has become the director of a theatrical museum since the death of her husband 10 years earlier, reads in a Chicago newspaper that her dead husband's elder brother, Raymond, has died in a fire at the family's summer place on Martha's Vineyard. The young widow decides to visit the family to pay her condolences, despite the fact that its members threaten to swallow her with their loving possessiveness.

When she arrives in Boston, Gillian finds that someone seems to be doing an very efficient job of killing off the Deckers. Raymond's son, Theo, died a horrific death four years earlier when a ransom could not be raised in time to pay off terrorists who had kidnapped him in Norway. Now three other teen-age nephews and nieces have died in bizarre "accidents" in less than three months -- on a ski slope, in a bathtub, and in a hit-and-run accident.

As a Decker in-law, Gillian joins the members of the family as they seek retreat at their enclave on Martha's Vineyard. There, as she tries to find some logical explanation for the string of family tragedies, she has a disturbing feeling of being manipulated in a clever game of charades.Murder in Detroit THERE ARE NO meaner streets than those in Jon) A. Jackson's Grootka (Foul Play/Countryman, $19.95). This is Detroit, a big city sinking into a morass of crime and neglect, abandoned by a middle class that has fled from the urban problems, the fire-gutted buildings, the littered, overgrown lots and the dangerous streets.

It does seem "the right place to find a corpse." In Grootka, one is found in a car trunk, and this leads to the reopening of the more than two decades old rape-murder case of a teen-age girl. The body is that of the snitch who led police to the arrest of a suspect who later escaped.

The rape-muder case has haunted retired cop Grootka over the years. Now, with the murder of the snitch and an old woman who figured in the case, Grootka feels that the psychopathic killer may have surfaced again and is seeking revenge. He enlists the help of his protege, Sgt. "Fang" Mulheisen, who has appeared in Jackson's two earlier Detroit police procedurals. This time Fang plays a supporting role to Grootka, the tough, old, streetwise cop who was his mentor.

The streets of Detroit are a grim, depressing background. Yet Jackson manages to make the friendship between the two cops, who work on the dark side of life, strangely touching -- even redeeming -- at the end. All About Eve A MODEST mystery, strong on regional flavor and local color, marks the debut of Eve K. Sandstrom in Death Down Home (Scribners, $18.95).

Nancy Titus, quite a charmer as the narrator, has hated small towns since her childhood experiences as an Army brat. But she is determined to accompany Sam, her new husband, to Holton, a dot on the map of Oklahoma's ranch country, when he is called back from Germany to the bedside of his gravely-injured father. The young bride is puzzled and hurt when Sam, an officer in the Army's Criminal Investigation Division, becomes uncommunicative and withdrawn.

Nancy feels like an outsider in the clannish small-town. And Sam continues to offer no comfort as he pursues a suspicion of foul play in the "accident" of his father and the disappearance of his brother. In the end, it is Nancy's talent as a photographer that provides the vital clue that leads to a surprising murderer.

In Death Down Home, Sandstrom evokes the dusty flatlands of Oklahoma where the trees grow leaning with the prevailing wind. You feel the oppressive heat and see the unending horizon. But Sandstrom's prose style can be labored at times, and she makes Sam so boorishly insensitive to the engaging Nancy's feelings that you begin to doubt that the marriage will survive.

Jean M. White regularly reviews mysteries for Book World.