TALLAHASSEE, Fla. (AP) _ Attorney general-elect Bob Butterworth said he did not think the murder- suicide of his former wife and 16-year-old son could have been prevented since no one realized the extent of her mental troubles.

Butterworth spoke Tuesday for the first time with reporters about the killings, which occurred the day before the Nov. 4 elections in which he easily defeated state Rep. Jim Watt for the attorney general's office.

Miami police said Saundra Butterworth, 43, apparently timed the killings of 16-year-old Robert Butterworth III, their only child, and herself for revenge. Some friends said she was still bitter about the couple's 1976 divorce.

''There is just no way anyone could have prevented it. No one thought she could do anything like this,'' said Butterworth, speaking at times with difficulty.

Butterworth went into seclusion and canceled all election celebrations after the deaths.

No one thought anything unusual when Mrs. Butterworth picked up her son from high school Nov. 3, something she did it routinely, Butterworth said.

She eventually drove her son to a Northeast Miami street, shot him four times in the chest and neck, called police and then shot herself once in the head.

Mrs. Butterworth's friends had said she recently had seemed been disturbed and paranoid. Butterworth confirmed that family and friends tried to persuade her to undergo psychiatric counseling, but she refused because she thought it would hurt her career as a lawyer.

The gun used in the shootings was a five-shot, .38-caliber revolver. Butterworth, who remarried two years ago, said he once carried such a gun serving as legal adviser to the Broward County Sheriff's Department in the early 1970s, and his wife kept it after they separated.

Butterworth's son had led a sheltered life until recently because he suffered from severe allergies. Campaign officials said the teen-ager appeared to be growing out of some of the medical problems.

''Obviously Bobby was a large part of my life,'' Butterworth said. ''It's a tragedy (for) a person with a very talented future - his life was cut short. His mother also was a very bright person who could have had a very bright future.''