Discussion

The findings of this review highlight the presence of recurrent criminological and forensic features in intimate partner femicide (IPF) across different geographical contexts. Although the included studies are heterogeneous in design and scope, several converging patterns emerge from the comparative analysis, particularly with regard to victim–perpetrator relationships, contextual dynamics of the homicide, and selected psychiatric risk factors [37, 51, 52].

The data do not support the identification of intimate partner femicide as a distinct legal category of homicide; however, they suggest that IPF is characterized by specific relational and contextual elements that differentiate it from other forms of lethal violence. From a medico-legal perspective, the recognition of these recurring features may contribute to improved risk assessment, preventive strategies, and interpretative frameworks in both forensic and judicial settings [36, 51].

Across the included studies, victims were most frequently adult women involved in long-term intimate relationships, often characterized by prior interpersonal violence and shared domestic or familial contexts. Perpetrators were predominantly current or former cohabiting partners, with limited regional variability reported in this regard. These observations, derived from population-based and forensic series, underscore the relevance of relational dynamics in the analysis of IPF cases [49, 52].

Several studies further identified the period following relationship separation as a particularly vulnerable phase, during which the risk of lethal escalation appears increased. In cases involving former partners, a substantial proportion of homicides occurred within the first year after separation, highlighting the temporal dimension of risk in IPF and its relevance for preventive and protective interventions [50, 52].

Methods of killing and weapon availability

Across the included studies, marked geographical differences were observed in the methods used in intimate partner femicide (IPF). In population-based and registry studies conducted in high income countries, particularly in the United States and Western Europe, firearms emerged as the most frequently used weapon in IPF cases, whereas sharp-force injuries represented the second most common category [37, 42, 51].

In contrast, forensic and registry-based studies from low–middle income countries reported a higher prevalence of strangulation, blunt-force trauma, and sharp-force injuries, with firearms being less frequently involved [41, 43, 45].

These differences appear to be primarily related to variability in weapon availability and accessibility across regions. In countries with widespread civilian access to firearms, the presence of guns in domestic environments may facilitate their use during episodes of intimate partner violence, whereas in settings where firearms are less accessible, perpetrators more frequently resort to weapons readily available in the household, such as knives or to manual methods such as strangulation [37, 44]. From a medico-legal perspective, the method of killing has relevant implications for both injury patterns and investigative reconstruction. Autopsy-based studies consistently reported that strangulation and blunt-force trauma were frequently associated with multiple injury mechanisms and defensive wounds, reflecting intense physical confrontation between victim and perpetrator [46, 47].While sociocultural factors may contribute to shaping patterns of violence, the available empirical data primarily support an interpretation centered on structural differences in weapon accessibility rather than on specific cultural or symbolic meanings attributed to the act itself. Accordingly, explanations based on broader cultural or normative frameworks should be considered cautiously and remain secondary to the forensic and epidemiological evidence provided by the included studies.

Setting

Across the included studies, the domestic environment emerged as the most frequent setting for intimate partner femicides. Population-based and forensic series consistently reported that the majority of IPF cases occurred in the victim’s home or in a shared residence with the perpetrator, whereas a smaller proportion took place in public spaces or other locations [42, 51, 52].

The predominance of the domestic setting appears to be closely related to the relational nature of IPF. Several studies described a background of prolonged intimate relationships characterized by prior interpersonal violence, shared living arrangements, and progressive escalation of abusive behaviors, which may facilitate lethal events within the domestic environment [37, 49].

From a forensic and medico-legal perspective, the domestic setting has relevant implications for both risk assessment and investigative reconstruction. Autopsy-based studies frequently reported evidence of prolonged physical confrontation and defensive injuries in cases occurring within the home, suggesting intense interpersonal dynamics preceding the fatal event [46].

Although theoretical models of coercive control have been proposed to explain the centrality of the domestic environment in intimate partner violence, the empirical findings of the included studies primarily support a descriptive interpretation centered on relational proximity, shared living spaces, and opportunity structures. Accordingly, broader psychological or sociological interpretations should be considered complementary to, but not substitutes for, the forensic and epidemiological evidence.

Prior domestic violence and escalation patterns

Several of the included studies reported a documented history of prior interpersonal violence preceding intimate partner femicide. In population-based and forensic series, victims had frequently experienced repeated episodes of physical, psychological, or combined forms of abuse before the lethal event, suggesting a progressive escalation of violence over time [37, 51, 52].

When reported, prior violence often occurred within the context of long-term intimate relationships characterized by cohabitation and shared domestic environments. These relational and contextual elements may contribute to the persistence and intensification of abusive behaviors, ultimately increasing the risk of lethal outcomes [42, 49].

From a medico-legal perspective, the presence of a documented history of domestic violence has relevant implications for both risk assessment and prevention. Several studies emphasized that prior episodes of abuse, when identifiable through medical records, police reports, or forensic documentation, represent critical warning signals that may precede intimate partner femicide [51, 52].

While theoretical models describe domestic violence as a dynamic process involving escalation and increasing control, the empirical evidence provided by the included studies primarily supports a descriptive association between repeated prior abuse and the occurrence of IPF. Accordingly, interpretations extending beyond documented patterns of prior violence should be framed cautiously and distinguished from the observed data.

Jealousy as a relational motive: medico-legal considerations

Several of the included studies identified jealousy and possessive behaviors as recurrent relational factors in cases of intimate partner femicide. In these contexts, jealousy was most frequently described as a motive reported in judicial records, witness statements, or case reconstructions, rather than as a formally diagnosed psychiatric condition [36, 51].

Importantly, the available evidence does not support the interpretation of jealousy as an independent psychopathological entity in the majority of IPF cases. Instead, jealousy appears to function as a relational and behavioral pattern, often embedded within dynamics of control, possessiveness, and fear of abandonment, particularly in the context of relationship conflict or separation [49, 52].

From a medico-legal perspective, this distinction is crucial. While pathological forms of jealousy may occur within specific psychiatric disorders (e.g., psychotic or substance-induced conditions), most cases described in the included studies involved non-delusional jealousy, expressed through controlling behaviors, threats, or escalating interpersonal violence. As such, jealousy should be interpreted primarily as a contextual risk factor rather than as a determinant of criminal responsibility.

Several studies emphasized that jealousy-related behaviors frequently intensified during periods of relational instability, particularly following separation or perceived threats to the relationship. In this phase, jealousy may interact with other risk factors—such as prior domestic violence, substance abuse, and access to weapons—contributing to an increased risk of lethal escalation [50, 52].

Accordingly, the relevance of jealousy in intimate partner femicide lies less in its psychiatric classification and more in its value as a warning signal within risk assessment frameworks. From a forensic standpoint, the identification of jealousy-driven behaviors in medical, legal, or social records may contribute to the early recognition of high-risk situations, without implying the presence of a mental disorder.

Psychiatric disorders and substance abuse: forensic implications

Across the included studies, psychiatric disorders were reported in a minority of perpetrators of intimate partner femicide. When available, data indicated that severe mental disorders, including psychotic disorders, were present in approximately 5–10% of cases, whereas broader psychiatric symptomatology at the time of the offense—such as depressive or anxiety symptoms—was described in a higher but still limited proportion of perpetrators [34, 48, 51].

These findings suggest that most perpetrators of IPF do not meet criteria for severe mental illness and that psychiatric disorders alone cannot account for the occurrence of lethal violence. Rather, mental health conditions appear to function as contributing or amplifying factors when combined with relational conflict, prior domestic violence, substance abuse, and situational stressors, particularly during periods of relationship instability.

Substance abuse emerged as a more consistently reported factor across multiple studies. Chronic alcohol or drug abuse was documented in approximately 15–20% of perpetrators overall, with higher rates reported in specific national series. Alcohol was the most frequently involved substance, followed by illicit drugs such as cocaine, methamphetamines, marijuana, and heroin [49, 51]. Toxicological positivity at the time of the offense or a documented history of substance abuse was associated with increased impulsivity and reduced inhibitory control, potentially facilitating violent escalation.

From a medico-legal perspective, the presence of psychiatric disorders or substance abuse should therefore be interpreted within a multifactorial framework. While specific psychiatric conditions—particularly psychotic disorders or substance-induced states—may be relevant for individual assessments of criminal responsibility, the empirical evidence provided by the included studies does not support a general causal attribution of IPF to mental illness.

Accordingly, the forensic relevance of psychiatric factors in IPF lies primarily in their contribution to risk assessment, prevention strategies, and individualized medico-legal evaluation, rather than in their use as explanatory models for the phenomenon as a whole.

Autopsy

There is a clear connection between the injuries observed during autopsies in femicide cases and the dynamics of domestic violence, coercive control, and the psychology of the perpetrator. Autopsies in these cases often reveal violent methods such as strangulation, stabbing, blunt force trauma, and sexual abuse, all of which are key indicators of an escalation of violence that frequently culminates in homicide.

These injuries, when analyzed in conjunction with cultural and social factors, provide valuable insights into understanding the phenomenon of femicide on an international level [4, 50–53].

Here are some indicative percentages based on global studies and reports on femicides:

Firearms: Firearms are used in a variable percentage of femicides, but they are generally a common weapon in intimate partner femicides (IPF). In countries where firearms are easily accessible, particularly in high-income countries [i.e. United States of America], the majority (45.2%) of femicides are committed using firearms.Strangulation: Strangulation is one of the most common methods (27.1%) of femicides in low-middle income countries with restrictions on firearm access. It is followed by blunt force trauma (25.0%) and poisoning (16.7%).Stab Wounds: Stab wounds are frequently observed in femicides, especially in countries where firearms are less accessible. Around 25–30% of intimate partner homicides involve the use of knives or similar sharp objects.Head Injuries and Contusions: Head injuries and cranial trauma are very common in femicide cases related to domestic violence. Around 20–30% of intimate partner homicides involve head injuries, including skull fractures, brain hemorrhages, hematomas, and visible bruising. These are often associated with violent beatings or blunt force impacts.Defensive Wounds: Defensive wounds (bruises, abrasions, or fractures resulting from the victim’s attempts to protect themselves) are common in femicides, as victims often try to resist or escape. On average, 25–30% of victims show defensive wounds, which are indicators of a struggle between the victim and the aggressor before the death.Combination of Injuries: In many femicide cases, there is a combination of different types of injuries, suggesting an escalation of violence. This could include a mixture of strangulation, blunt force trauma, and stab wounds, indicating the aggressor’s increasing aggression .

The percentages presented are general estimates based on various international studies. It is important to note that specific data may vary between countries and contexts, influenced by factors such as weapon availability, domestic violence culture, and access to support resources for victims. However, strangulation, stab wounds, head trauma, and defensive injuries are the most commonly observed types of injuries during autopsies in femicide cases. These data are essential for understanding the dynamics of domestic violence and developing preventive strategies to reduce femicides globally [46, 47, 54–56] (Fig. 2).

Fig. 2: Diagnosis of femicide should derive from a global consideration of each feature discussed above, and reported in Fig. 1