Motive

motivation/ 2: a motivating force, stimulus, or influence: INCENTIVE, DRIVE Merriam-Webster’s Collegiate Dictionary, Eleventh Edition


Motive: The emotional, psychological, or material need that impels, and is satisfied by, a behavior. Brent Turvey, Criminal Profiling: An Introduction to Behavioral Evidence Analysis


Motive and intent both involve state of mind. They are, however, legally distinct. Intent is when you decide to use a particular means to accomplish an act. Motive is what makes you do it. DAs must prove intent. They don’t have to prove motive, but because jurors are human they want to know why. In 1973 and 2006, prosecutors believed Duane had two motives for killing his wife: Barbara Dean, and Betty’s life insurance.

Betty had two insurance policies with Martin Marietta: life with a face value of $8,000 and a double indemnity accident clause, and a $100,000 accidental death policy. Duane was the sole beneficiary of both. If he was 48 or older when she died, he also received $175 a month until age 62. Duane turned 48 exactly two weeks before Betty’s murder. In 1973, Martin’s insurance administrator estimated Duane’s payoff at $149,000. That’s $850,000 today.

Attraction to another woman and being sole beneficiary of a big insurance policy are rational motives for murder. DAs believe they are far easier to sell to a jury than the complexities of a man who felt deceived by his wife and a world that refused to recognize his primacy and worth.

After working at four other companies as an industrial engineer specializing in efficiency and production problems, Duane went to Martin in 1956. Martin competitively ranked employees on a “totem pole”. Duane’s rank determined whether he was promoted from technical engineer to the increasingly responsible management positions to which he aspired. After the murder, his co-workers painted a picture of a man who’d been struggling to maintain his grip.

Duane had been one of the first to volunteer to go to Huntsville to get Martin’s Sky Lab off the ground. Less than a year later he returned to the Denver-area plant. One colleague told the cops Duane was frustrated and couldn’t work with customers in Alabama. Duane’s always been outspoken, another said, he couldn’t hold his tongue; he’d have his say, then calm down and revert to his normal self. A third saw him angry a couple of times and said he was very intelligent but also very impatient and abrupt. In October 1972, seven months before Betty was murdered, Martin laid Duane off.

Duane framed entering private consulting as his decision, a time he could finally strike out on his own. If he was to succeed, he knew he had to work the problem of his interpersonal skills. He enrolled in a Dale Carnegie course.

Is a rational motive more convincing than a psychological one?


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