As usual, these things tend to follow patterns:
"In almost every case, the familicide is premeditated and the perpetrator views his family members as property, such that he maintains the right to end their lives (Scheinin, Rogers, & Sathyavagiswaran, 2011, p. 327). Regardless of motive or history, this typically stems from the belief that they are solely responsible for their family’s needs (Marzuk, 1992, p. 3181). Perpetrators need to maintain their masculinity, which is tied to the family unit, as well as control and power over their family members. When these factors are threatened, they act out against the family violently and fatally (Yardley, Wilson, & Lynes, 2014, p. 131). When fearing abandonment, offenders adopt a Medea complex (‘if I cannot have them, no-one can’), exemplified through the murders (Liem & Koenraadt, 2008, p. 315)...
A review of familicide literature across various different times and locations revealed repeated patterns of dissatisfaction, marital strife, possessive and controlling tendencies, as well as economic, emotional, verbal, physical, sexual, and social domestic abuse. Most offenders also threatened to hurt themselves and/or others, including their spouse, if the spouse attempted to leave the offender or have extramarital relations (Johnson & Sachmann, 2017, p. 139). Marital disputes, isolation from the spouse, divorce, and custody disputes over children are other accelerants to familicide, as the offender becomes overly focused on violent behavior as a means of stress relief (Scheinin et al., 2011, p. 329)...
Remorse. All surviving fathers insisted that they previously loved and continue to love their children deeply, displayed signs of mourning, and described their children’s murder from the perspective of a bystander. The fathers separate themselves from their crimes, viewing their anger as the offender rather than the self. In their rage, all objects were viewed as evil and in need to be destroyed. Post-offense reflection shows dichotomized views of the murdered, such that the suffering caused by the family member and their murder are separated from the actual individual and their immortalization in the mind of the offender (Malmquist, 1980, p. 303)...
The typical perpetrator of familicide is the male head of household who is either depressed, paranoid, or intoxicated (Marzuk, 1992, p. 3181). Common themes emerge among all familicide perpetrators. For one, offenders hold the belief that they have a right over their family members’ lives (Scheinin et al., 2011, p. 329). Relatedly, they maintain the need for power, such that murder begets feelings of control (Fox & Levin, 2003, pp. 58-59). In most cases of familicide, the spouse was the primary source of the offenders’ anger, where the children were viewed as supporters or extensions of their mother (Wilson et al., 1995, p. 289)...
The hostile accusatory offender is angry at his spouse for infidelity and/or attempts to separate and he often expresses open displays of violence and anger prior to the murder...
More recently, in a 2008 analysis of offenders with disabilities, four distinct categories of offending motives were rendered: narcissistic rage (26%), psychosis (22%), fear of abandonment (22%) and ‘other’ (30%) (Liem & Koenraadt, 2008, p. 313). The accepted profiles today are selfrighteous, disappointed, anomic, and paranoid (Yardley et al., 2014, p. 131)...
Self-Righteous. The most common classification, categorizing 32% of offenders, was the self-righteous profile. These perpetrators blame their spouse for the collapse of the family unit and all other life problems, which elicits a desire to retaliate against them. This offender type holds the nuclear family unit and their sole ability to support them at the center of their masculinity. The family is viewed as a failure when the father cannot provide or other people provide in place of him for the family. The offender attempts to regain control and power by eliminating the family whom he designates is the primary threat against his success. This offender often has a history of controlling, narcissistic, and dramatic behavior, which may also occur during the murders (Yardley et al., 2014, pp. 131-133)...
Disappointed. The disappointed offender also views the family as vital to his masculinity and maintains that the family must represent the offender’s idyllic representation of a family unit to be successful. When the family does not conform to this prototype, the perpetrator becomes outraged and views the family as a failure. His solution to this problem is to destroy the family through murder. These offenders represented 29% of total familicide offenders (Yardley et al., 2014, pp. 134-135)...
All offenders categorized as self-righteous offenders were primarily motivated by family breakdown. Domestic violence and separation were prominent features in these cases. Multiple cases had features of jealousy, custody disputes, and spousal affairs. Offender histories of mental illness or legal involvement were also present in some cases. 80% of self-righteous offenders killed their victims by shooting and only one offender used multiple methods of murder. All but two of the self-righteous offenders committed suicide."
This was the best compilation of studies I have seen, regarding family annihilators. So much more at link (49 pages).
