Women (acting alone) don’t kill* (except to defend themselves or others) unless they have some MAJOR problem ( like drug addiction, severe depression or other severe mental illness, history of abuse ) or a strong MOTIVE ( typically financial or other material gain, or in crimes of passion, betrayal ).
Exclusions: Acts of War or Political Intrigue.
* By “kill” I mean kill another person or persons.
Counter-examples welcome here or here, but please check all conditions are satisfied.
List of non-counter-examples:
There was a comment:
Not at all true, women are just as evil as men when it comes to murder. See: http://mentalfloss.com/…/8-sensational-female-murderers… ] Add to that Karla Homolka; Aileen Wuornos; Rosemary West; The “Blood Countess” Elizabeth Bathory; Lizzie Bordan; and Bonnie Parker of “Bonnie & Clyde” infamy.
Working through the list of 8:
1. Marie de Roux Manning : did not act alone, motive was financial or material gain.
Over the next two days, Marie cleaned out what valuables, cash, and stock certificates she could find at O’Connor’s home.
2. Constance Kent : is about as clear as mud, was 16 years old, and may have had the motive of competing against step-siblings.
3. Belle Gunness : financial motive.
4. Dagmar Overbye : financial motive ( paid to care for babies, murdered them instead ).
5.Jane Toppan : insane multiple poisoner. Found not guilty by reason of insanity, and was held in a mental institution for the rest of her life.
6. Mary Ann Cotton : murdered husbands, step-children ( motive, to favour her own interests ).
7. Amelia Dyer : another baby-farm murderer, financial motive.
8. Tillie Klimek : poisoned husbands for insurance money.
And the others:
1. Karla Homolka : didn’t act alone.
2. Aileen Wuornos : unusual serial self-defence claim, history of abuse.
3. Rosemary West : didn’t act alone, history of abuse.
4. The “Blood Countess” Elizabeth Bathory : a legend (died 1614). Witnesses may have been coerced : “All but one of the Countess’s servants testified against her–the one who refused had her eyes gouged out and her breasts removed before being burned at the stake.”
5. Lizzie Bordan : not clear : acquitted.
6. Bonnie Parker of “Bonnie & Clyde” infamy : didn’t act alone!
See also Instrumental versus Expressive violence and Psychopaths and Serial Killers.