Gender and age
In the literature, the majority of complex suicide cases were male (Banchini et al. 2017; Demirci et al. 2009; Racette and Sauvageau 2007). Barranco et al. (2019) stated that 84% of the complex suicide cases they presented were male. In this study, most cases were also male (81%). Men chose more violent methods of suicide than women, and their death rate was higher than women’s; therefore, it was predictable that complex suicides would predominantly involve male victims.
In the literature, although complex suicides mostly occurred at home, they occurred in different areas (Kučerová et al., 2019; Pélissier-Alicot et al. 2008; Simonit et al. 2018; Vidhate et al. 2016). In Turkey, most of the complex suicide victims committed suicide at home (Demirci et al. 2009). In this study, 18 of the 21 cases (85.7%) committed suicide at home.
Suicide notes and suicide attempts
The suicide note is one of the most important pieces of evidence in making the distinction between a murder and a suicide in complex suicide deaths (Demirci et al. 2009; Kuwabara et al. 2006; Racette and Sauvageau 2007; Töro and Pollak 2009). Victims leave a suicide note in 20–50% of complex suicides (Demirci et al. 2009; Racette and Sauvageau 2007; Töro and Pollak 2009). In this study, suicide notes were present in 6 (28.5%) of 21 cases. A history of previous suicide attempts may also be considered a useful argument for a homicide-suicide distinction like the suicide note (Racette and Sauvageau 2007); 15–30% of victims of complex suicides have a history of previous suicide attempts (Demirci et al. 2009; Racette and Sauvageau 2007; Töro and Pollak 2009). In this study, five cases (23.8) had previously attempted suicide. In complex suicides, the existence of a previous suicide attempt appears to be less than the suicide note. However, it should not be forgotten that previous suicide attempts may have been overlooked if the victim’s past was not completely revealed in the police investigation or if the family members did not want to talk about the victim’s previous suicide attempts. For such cases, it will be significant to examine the hospital admission records in the distinction between suicide and homicide.
Psychiatric disease and suicide motivation
In complex suicides, many case reports include victims with psychiatric disorders including bipolar disorder, schizophrenia, depression, and depressive symptoms (Cascini et al. 2012; Christin et al. 2018; Dogan et al. 2014; Germerott et al., 2010; Pélissier-Alicot et al. 2008; Racette and Sauvageau, 2007; Simonit et al. 2018). Banchini et al. (2017) associated complex suicide cases with borderline personality disorder, major depression, bipolar disorder, and schizophrenia. Demirci et al. (2009) showed that 62.5% of complex suicide cases had been diagnosed with a psychiatric disease, and 50% of cases’ suicide motivation source was psychiatric diseases. A history of a previous suicide attempt is one of the basic elements of complex suicide cases; in this study, 71.4% (n: 15) of the victims had a psychiatric disease, and 13 (61.9%) cases’ suicide motives were a psychiatric disease, which was in accordance with the literature. Victims of complex suicide may be diagnosed with depression, schizophrenia, psychosis, bipolar disorder, anxiety disorders, and antisocial personality disorder (Banchini et al. 2017; Demirci et al. 2009; Simonit et al. 2018). In this study, there were diagnoses of depression (n: 8), schizophrenia (n: 1), psychosis (n: 5), and anxiety disorders (n: 1) in the complex suicide cases.
Methods of suicide
The most commonly used suicide method in this study was to take one or more drugs in lethal or toxic doses. In unplanned complex suicide cases, victims most often stab themselves or jump from a great height. In planned complex suicides, the victims most frequently preferred to take one or more drugs in lethal or toxic doses as a method of suicide. Bohnert (2005) claimed that the widespread use of hypnotics and other sedative drugs in planned suicides is one of the most common suicide methods in general, although the victim may also be using these drugs to reduce the pain of the second suicide method. Racette and Sauvageau (2007) noted that it would be difficult to distinguish whether the motivation for using hypnotic and other sedative drugs was to prevent the pain of the second suicide method or to actually kill the victim. To avoid this confusion, they suggested that these events should be classified as “drug-related complex suicides” and “drug-unrelated complex suicides.” However, based on crime scene investigations and autopsy findings, Demirci et al. (2009) argued that drug intake in complex suicides can easily be demonstrated as for suicide purposes, and lethal and toxic drug overdoses should also be evaluated in these cases. In this study, we determined that 12 cases had taken one or more drugs at lethal or toxic doses for suicide by evaluating the crime scene investigation and autopsy findings. Studies conducted in Turkey have reported that the most commonly used suicide methods were hanging, the use of firearms, jumping from high places, and taking medications (Asirdizer et al. 2010; Enginyurt et al. 2014). In addition, emergency department studies demonstrated that more than half of the poisonings that occurred for suicidal purposes involve the intake of drugs; the most commonly used drugs were antidepressants, antipsychotics, and analgesic medications (Avsarogullari et al. 2012; Kavalci et al. 2012; Satar et al., 2009). Since drug overdoses are one common suicide method used in Turkey, this approach was included in this study as a method often used in complex suicides.
In planned complex suicides, two or more methods with high mortality rates are used at the same time to ensure death even if one method fails (Sanjeewa and Vidanapathirana 2017). In unplanned complex suicide, after the first suicide method is unsuccessful, other methods with a higher probability of death are attempted (Banchini et al. 2017; Demirci et al. 2009; Kučerová et al. 2019; Racette and Sauvageau 2007). Eleven of our 21 cases were evaluated as planned complex suicides, and 10 of them were labeled unplanned complex suicides. In the latter group, the victims often selected methods with a low risk of death before methods with a higher risk of death; it is thought that the reasons for switching from a low-risk method to a high-risk method include pain, suffering, and disappointment (Demirci et al. 2009). The highest number of separate suicide methods used at one time in the literature was six (Petković et al. 2011). In this current study, three distinct approaches were used together as a suicide method in 2 cases, while two methods were used together in 19 cases. The most commonly used methods were “drug overdose + hanging (n: 3, 14.2%)” and “stabbing + jumping from a height (n: 3, 14.2%).”
Bohnert (2005) reported that the most commonly used combinations in planned complex suicide cases were taking hypnotic and other drugs + hanging, taking hypnotic and other drugs + drowning, taking hypnotic and other drugs + plastic bag suffocation, hanging + firearm injury, and firearm injury + drowning in water. Barranco et al. (2019) stated that wrist cutting + hanging was the preferred combination in complex suicides. In the Demirci et al. study (2009), insecticide ingestion + shotgun injury and insecticide ingestion + jumping from a height were first choice combinations. Racette and Sauvageau (2007) reported that the most commonly preferred method in planned complex suicide was the combination of hanging + firearm injury. The literature describes frequently used conventional methods in complex suicide as follows: firearm injury, hanging, jumping from a height, drug overdose, insecticide ingestion, drowning in water, self-strangulation, cutting, and stabbing (Ateriya et al. 2018; Hejna et al. 2012; Kaliszan et al. 2013; Kučerová et al. 2019; Peyron et al. 2018; Racette and Sauvageau 2008; Simonit et al. 2018; Vadsinghe and Thilakarathne 2018; Yin and Heard 2012). There are also cases that used rare methods, such as a vehicle accident, the use of electricity, foreign body ingestion, corrosive substance ingestion, eating plaster, self-burning, and nicotine patch use (Akçan et al. 2016; Bogdanović et al. 2019; Cascini et al. 2012; Christin et al. 2018; Dogan et al. 2014; Germerott et al. 2010; Karthik et al. 2013; Lardi et al. 2014; Pélissier-Alicot et al. 2008; Straka and Novomesky 2013; Vidhate et al. 2016;). In this study, the most commonly used methods were “medicine overdose + hanging (n: 3, 14.2%)” and “stabbing + jumping from a height (n: 3, 14.2%).”
A few cases of complex suicide have been related to the use of corrosive substances. Methods used in conjunction with corrosive substance intake include wrist cutting, stabbing, drug overdoses, and insecticide intoxication (Beltempo et al. 2015; Dogan et al. 2014; Petković et al. 2011; Vidhate et al. 2016). However, the combinations of “corrosive substance intake + jumping from a height” and “corrosive substance intake + cyanide intoxication” have not yet been described in the literature.
In the present study, one 33-year-old male victim was found dead in a car. A widespread erosive appearance and bleeding in the esophagus were detected upon autopsy. Hypochlorite was identified in a water bottle taken from the car at the scene, and a high amount of cyanide was found in the victim’s blood. It was concluded that the man died due to hypochloric acid intake and cyanide intoxication, and the case was classified as a planned complex suicide.
A 52-year-old man committed suicide by jumping out the window of his second-floor home. During the crime scene investigation, an open bottle containing hypochlorite was found on the outer ledge of the window. The autopsy revealed general body trauma, widespread erosive changes and bleeding in the esophagus, and hypochloric acid in the stomach contents. It was concluded that the man died from hypochloric acid intake and jumping from a height; he was classified as a planned complex suicide because he ingested the hypochloric acid outside the window and then jumped. Thus, forensic pathologists should keep in mind that different combinations of suicide methods that have not been previously defined can be used together in complex suicide cases.
Differential diagnosis between complex suicide and murder
The suicide note has an indisputable place in the complex suicide-murder distinction. Lesions detected in the victims should be in localizations that may be performed themself (Banchini et al., 2017). In this study, it was determined that all of the victims had lesions in localizations (wrist, abdomen, chest) that could be created by themselves. Penetrating stab wounds to the abdomen and chest usually do not cause visceral injuries (Banchini et al., 2017, Simonit et al., 2018). In this study, the internal organs were not injured in penetrating stab wounds to the chest and abdomen. Multiple superficial incisions (hesitating incisions) on victims' bodies are an important finding in favor of suicide (Barranco et al. 2019). Hesitation cuts were detected in the vast majority of victims who used stabs in this study. In addition, none of the cases had defensive wounds. Defense wounds are a strong predictor of homicide (Banchini et al., 2017; Barranco et al. 2019). History of psychiatric illness is considered one of the fundamental factors for complex suicides. (Banchini et al., 2017, Simonit et al., 2018) . In this study, the majority of the cases (71.4%) had a history of psychiatric illness.