DNA evidence in sexual assault cases in Pakistan

Introduction

Sexual assault is a growing serious concern all over the world, victimising members of both genders. Identifying offenders and choosing the right punishment is very important to both reduce and eradicate these crimes from society. The recognition of legal harm to the victim is a major measurement on which punishment is decided. Sexual assault can have a severe and adverse impact upon a victim’s life in Pakistan, owing to societal discrimination and humiliation. The victim has to pass through further adverse experiences in family gatherings, police stations and hospitals. A sexual assault therefore not only causes physical harm but also disturbs the well-being of the survivor. ¹

Sexual assault cases, as legally defined within Pakistan, include rape and anal sex (whether the latter is consensual or not) and they are reported across the country throughout the year. Unlike in many other countries, homosexuality and anal sex are unlawful in Pakistan and the person(s) involves in the criminal act are liable to imprisonment or a fine.

As regards sexual offences, Judicial proceedings and conviction mainly rely upon proper investigations and good prosecution. The role of modern DNA technology in identifying perpetrators of sexual offences is increasing gradually, however DNA evidence is not considered conclusive proof of sexual assault in the judicial system of Pakistan. The statements of victims and eyewitnesses are, however, considered primary evidence, while serological or DNA reports are recognised as corroborative evidence. DNA evidence has not attained the recognition in the courts of law in Pakistan which it has achieved in those of developed countries, such as the USA, UK and other European countries.^2–4

There are different laws which deal with sexual offences in Pakistan – for example rape is dealt under section 375 and 376 of Pakistan Penal Code 1860 (PPC, 1860), while anal, oral or any other form of sex is dealt under section 337 (PPC, 1860). These sections define the actions classified as sexual crimes and specify the punishments for these acts. Section 375 (PPC, 1860) defines rape as the penetration of the genital parts of a female by a penis. The penetration may or may not cause physical injury to the genital part of the victim, followed by the possible presence of the seminal material of the perpetrator. The availability of seminal material depends upon the condition, including whether the accused was discharged during coition; and if discharged, whether he discharged inside the vagina or outside on the body – for example on the groin, pubic area, thighs, hips, breasts or belly. If the accused performs sexual activity using a condom, there is no chance of obtaining seminal material from the female’s body. Section 376 (PPC, 1890) describes the punishment for rape, which is death or imprisonment of not less than ten years, or not more than 25 years. In cases involving the rape of a minor or a person who is insane, the offence is punishable by death, or imprisonment for life and a fine. Moreover, section 376A (PPC, 1860) also ensures that the identity of the rape victim shall not be disclosed to the public. Section 377 (PPC, 1860) deals with other types of sexual activity, categorising anal and oral sex alongside sex with animals or any unnatural sexual activity; and punishments are not less than two years or not more than ten years. According to this section, the penetration of the penis into anal or buccal cavities is sufficient to establish carnal intercourse.

Medical examination of the sexual assault victim

In cases of sexual assault the medical examination of a victim is necessary to obtain significant biological evidence to link a suspect to a crime and/or victim. Section 53A of Criminal Procedure Code 1898 (CrPC, 1898) authorises a police officer to take an accused (post-arrest) for medical examination to a nearby government hospital, where a medical examination is then carried out by a medico-legal officer (MLO) or casualty medical officer (CMO). For such medical examinations, the consent of the accused is not mandatory – that is, the accused cannot refuse to undergo a medical examination, and the police can use force where this is deemed necessary. Sections 164-A and B (CrPC, 1898) deal with the medical examination of a sexual assault victim. Under these sections it is the duty of the police to provide legal aid to the victim and a female victim should be escorted by a female police officer to the hospital. The examination is also carried out by female MLO or CMO after obtaining the consent of the victim if she is able to provide it; or after obtaining the consent of the parent or guardian, if the victim is a minor, unconscious or insane. Such consent is a prerequisite for the medical examination, and the police or MLO/CMO cannot force a victim to undergo such an examination against their free will.

Issues related to medical examination of the sexual assault victims

The medical examination of a sexual assault victim is very important in order to obtain the probative biological material of the accused for DNA analysis. Such medical examinations are conducted upon the request of police, or upon the direction of the court, and they are carried out in the nearby hospital. In the major cities of Pakistan, these hospitals have made arrangements for these medico-legal examinations, whereas in the countryside the hospitals often lack the necessary equipment or a female doctor. Therefore, the victim may have to travel to another city or place (sometimes more than 50km) to be examined, which may take a few days. In the majority of rape cases the medical examination of a victim is conducted more than 72 hours after the assault, for various reasons. These reasons include, but are not limited to, the fear of hostility and humiliation, shame, social pressure, the cynical attitude of police or the lack of availability of women medical officers in the hospital. ⁵

In Pakistan only medical doctors appointed as an MLO or CMO are legally authorised to conduct medical examinations of the victim and accused. Unfortunately it is common practice that these doctors do not in fact conduct these examinations, but instead they are performed by paramedical staff, despite the fact that they are neither trained nor authorised to undertake this work. Often the facts relating to sexual activity are not documented properly – for example contradictions of facts are observed in police records and medico-legal reports. However, the forensic interview of a victim is very important and can lead to the location of useful biological fluid on submitted evidence material.^6,7

In interviews the victim is questioned about the time since the assault, and whether he/she has had coition prior to or after the assault. Additional information, such as whether the victim has douched or taken a bath, passed urine or defecated, is important in sexual abuse cases. With the help of this information a DNA analyst can easily locate biological material of the accused on the submitted evidence. Often it is observed that these pieces of information are not submitted in writing by an MLO/CMO in medical reports. Moreover, rape kits are not available in most of the hospitals in Pakistan and medical staff use cotton-wrapped straw from sweeping brooms (Figure 1(a)) for swabbing vaginal and anal canals. Sometimes just a cotton clog (i.e. a lump of cotton) (Figure 1(b)) is used to insert into the vaginal canal of the victim to collect the seminal material.

OPEN IN VIEWER

Figure 1.

Different forms of swabs used for the collection of semen from the victim (a) Cotton plugs used as swabs (b) straw from broom wrapped with cotton.

Amid the lack of knowledge in advances in DNA profiling, medical doctors in Pakistan have little understanding of how to take swabs for DNA analysis from genitalia, or from other touched, kissed or smacked areas on the victim’s body, although it is reported that cells can be transferred even when one person shakes hands with another. ⁸ Therefore, if semen is not deposited inside or outside the body of the victim, the swabbing of the areas touched/kissed by the assailant may help to get his biological material. Swabs taken from the breast, cheeks, neck and other body parts of the victim can be useful for the DNA profiling and the identification of the suspect. ⁹

The improper packaging of vaginal and anal swabs can destroy the DNA on evidence material. It is observed that MLO/CMO used plastic or glass containers/bottles to package vaginal or anal swabs, instead of paper envelopes. The growth of fungus and other microbes along with a foul smell is being observed on the swabs when the bottles are opened in DNA laboratories for analysis. The spores of fungus and microbes are visible under a microscope when the slide is prepared for the examination of spermatozoa. A vagina is a cavity rich in various flora and fauna, and these microbes can easily grow on wet swabs in such conditions and may destroy potential evidence. ¹⁰ Mostly, no seminal material is found on such swabs because the microbes not only destroy sperm cells but also vaginal epithelial cells. If biological material is not completely degraded, few sperm cells can be recovered from swabs. But a low number of sperm cells would not give enough DNA to generate a complete DNA profile for comparison. Additionally, in gang rape cases the small quantities of male DNA can cause a difficulty with the correct interpretation of mixtures.^11,12

In some parts of the country police think that DNA profiles obtained from one type of tissue can only be compared with the DNA profile obtained from the same kind of tissue – that is, the DNA of the seminal sample can only be compared with the DNA obtained from semen and not with the DNA of any other tissue of the person. Therefore, police sometimes coerce the accused to donate the semen samples by masturbation, to provide a reference sample. This sample is stored in glass or plastic containers and sent to the forensic laboratory for analysis; however, it is usually degraded prior to analysis. The practice of taking a semen sample in this manner is practiced in many parts of the country, although it is contrary to the ethics and law of the land.

In Pakistan it is the practice for doctors to package all the clothing in a single cheesecloth or paper envelop, which may pose a threat of cross-contamination. Any piece of cloth, tissue paper or towel used to clean the genital area of the victim should be preserved and sent for the detection of seminal material from the accused. In the case of menstruation after a rape, the vaginal swabs are not good sources of seminal material. In such scenarios these pieces of evidence are useful. It was held that the presence of stains on trousers (shalwar) along with a history of injuries on the vagina or anus is conclusive proof of rape, even though no seminal material is found on the swab or clothing.^13,14 During the medical examination, combing pubic hairs of the victim (if these are long) is a good approach to find any hair foreign to the victim. Such hair may belong to the accused.

Injuries on the victim’s body

Injuries inflicted on the victim’s body during an assault to protect oneself are important to prove the occurrence of an offence. It is reported that in many cases of rape, physical signs of penetration or injuries on genitalia are absent. ¹⁵ In case of violent rape, injuries may be found on various parts of the body, including the genital area, vulva, labia, mons veneries, clitoris, hymen, pubic hair or anus. In anal sex, injuries can be observed on the anus, caused as a result of the penetration of a penis or finger through the anus and into the rectum. Tearing of the hymen can provide a clue, but it is not conclusive proof of penetration. It is reported that there are many other ways which a hymen can be torn, not just sexual intercourse. Similarly, it is also reported that the hymen can sometimes not be torn, even after penetration of the penis into the vagina, while on other occasions a torn hymen is unable to provide a clue regarding fresh coition.^16–18 In Pakistan the MLO/CMO performs the two-finger test to determine the virginity of the victim. In this process, she tries to insert two fingers into the victim’s vagina to check the rupture of the hymen. It is held that even penetration of one finger can constitute rape and sometimes the vaginal opening may constrict after intercourse. ¹⁹

Interpretation of a DNA report

Forensic DNA testing, also known as DNA profiling or DNA fingerprinting, is used to establish the identity of an accused, victim or any other person linked to a crime. Forensic DNA analysis ends up with three types of conclusions – that is, inclusion or a match, exclusion or no match, and inconclusive. When a DNA profile from evidence material matches with a DNA profile of a known person – that is, victim or suspect – inclusion or match is stated in the report. When a DNA profile from evidence is not consistent with the DNA profile from known/reference samples, the result of the DNA test is an exclusion. This means the suspect or victim is eliminated as being the source of DNA obtained from evidence material. In some cases it is difficult to reach a conclusion regarding the contribution of a person to the DNA profile obtained from the evidence. In such cases the result of DNA analysis is reported as inconclusive. Inconclusive results are usually observed due to various reasons, including low template DNA or degraded DNA, or a partial mixture of more than three contributors. The interpretation of inconclusive results requires good knowledge, skills and experience.^20–22

It is observed that many in the legal community, including lawyers and judges, are not properly educated regarding forensic DNA analysis. Many of them are not aware of the technical issues relating to forensic DNA reporting. Sometimes it is difficult for them to comprehend the exact meaning of the report. As a result of these limitations, the significance of a DNA report may be negotiated, especially in low-template DNA samples, mixed profiles or Y-STR analysis, when two or more than two accused in a case are paternal relatives.

DNA evidence in the legal system of Pakistan

Qanun-e-Shahadat Ordinance 1984 (QSO, 1984) deals with the admissibility of DNA evidence in judicial proceedings in Pakistan. Article 59 (QSO, 1984) allows the admissibility of expert opinion in a court of law, considering it relevant fact. Article 164 (QSO, 1984) deals with the application of modern devices to obtain the facts in a case. A DNA report is considered to be an opinion of an expert on the DNA recovered from evidentiary material. Apart from these, there is no legislation in the form of substantive enactment upon the admissibility of DNA evidence during a judicial trial. In finalising the inquiry before trial, serology reports are a prerequisite under section 510 (CrPC 1898). So, considering DNA as a chemical, the DNA report is admissible in judicial proceedings under this section. Sindh province has inserted two new sections – that is, 156-C and 156-D – in the Code of Criminal Procedure, 1898 (CrPC, 1898). According to these sections, the police are responsible for managing the medical examination of sexual assault victims within 72 hours. The police and forensic laboratories are now responsible for storing and preserving the biological evidence obtained from the victims of sexual assault. In Salman Akram Raja v. Government of the Punjab, ²³ the Supreme Court opined that the government should take the necessary measures to get justice for the assault victim. It was held that the DNA test should be made mandatory in rape cases, however not much has been done by the government in this regard to date. For Khyber Pakhtunkhwa (KP) province, the Peshawar High Court gave a ruling in rape cases that DNA testing of the rape victim should be carried out compulsorily under section 164 (CrPC 1898) and the Protection of Women (Criminal Law Amendment) Act, 2006.²⁴

The use of DNA evidence in deciding crimes of sexual violence has gradually gained more attention from the courts. In 2011, In Khadim Hussain v. the State, ²⁵ the DNA profile obtained from evidence item did not match the DNA profiles of the accused, however the accused was convicted by the trial court and the decision was maintained by the Federal Shariat Court. Later in 2013, the Federal Shariat Court of Pakistan observed that no accused should be convicted in the cases of rape (Zina) without a DNA report. ²⁶ This judgment laid the foundation for the reliability of courts on DNA evidence in deciding rape cases in Pakistan. In the case of Allah Ditta v. the State ²⁷ and Tanveer Ahmad v. the State, ²⁸ the courts acquitted the accused, considering that charges of rape were not proven through DNA reports. In Yasir and other v. the State, the accused was tried for the charges of the commission of rape. ²⁹ The DNA from Shalwar (trousers) of the victim matched with the DNA profile of the accused, therefore the accused was convicted. The court also considered other pieces of evidence in the case, which supported the credence of the prosecution’s proposition. The courts in Pakistan are giving heed to DNA reports in sex crimes for establishing the crimes.

Moreover, the admissibility of a DNA report in assault cases remains in doubt, as a result of conflicting decisions of the apex court. It was held that the opinion of a victim is of primary importance and the DNA report cannot substitute its position, although in granting bail to the accused the court mainly relies upon the DNA report. If the DNA of the assailant is not found on vaginal or anal swabs or the clothing of the victim and there is no other concrete evidence, the courts usually grant him bail. The courts consider a forensic DNA report as corroborative evidence or secondary evidence. In Muhammad Ameen v. the State, ³⁰ Lahore High Court refused to grant post-arrest bail, although no male DNA was found on a vaginal swab of the victim. The court had considered the DNA report as secondary evidence with no legal value because it was contrary to the primary evidence (victim’s statement). The accused was an Imam (cleric) in a mosque, who allegedly raped his student. The student’s father lodged a First Information Report (FIR) against the accused of raping his daughter. In this case the court held that no father would like to falsely implicate a person by taking the risk of stigmatizing his daughter. In Wishal Masih v. the State, ³¹ the Lahore High Court upheld a decision of conviction by the trial court although no male DNA was obtained from vaginal swabs. The court opined that a negative DNA report did not support the defence proposition, since the injuries of the genital area of the victim mentioned in the medico-legal report supported the veracity of the statement of the victim. Similarly, in the Fort Monro gang rape case five accused were alleged to have raped five girls. The DNA of one of the accused was found on vaginal swab of one of the victims, however, regardless of the DNA report, the trial court acquitted all the suspects because the victims declined to identify them. So, the presence of seminal material on the vaginal swab of a victim is of less evidentiary value compared to the statement of a victim.^33,34 Judicial responses to DNA evidence in India are the same as those in Pakistan in sexual assault cases. ³⁵ In developed countries, such as the USA, UK and some other European countries, the court mainly relies upon DNA evidence during trials.

Competency of expert testimony

Over the course of time, DNA evidence has gained weight in the eye of judges, who started relying on DNA reports for deciding cases. The admissibility mainly depends upon the discretion of a judge, who acts as a gatekeeper and allows the submission when convinced by the subject matter of the report. There is no guiding rule or principle available in Pakistani law which can be used to check the authenticity and qualification of the expert. There are two guiding principles in America which are considered as standard for admissibility of forensic evidence – that is, the Frye test^32,33 and Daubert test. ³⁴ These two case laws determine the qualifications, skills, knowledge and experience of an expert who testifies, along with the opinion he makes and the technology used in making such opinion. ³⁵ Rule 702 of the Federal Rules of Evidence USA, formulated based on these two case laws, clearly explains the possibilities of accepting forensic evidence during judicial trials, even in the presence of any discrepancies or shortcomings. Section 293 (CrPC, 1898) of India also deals with the cross examination of the forensic expert report/testimony in order to ensure the competency of experts and the authenticity of technology used during examination of the physical evidence. In the DNA Evidence Act (2016) India has formulated guiding principles for eradicating shortcomings in the DNA test and in expert opinion. This Act deals with the data/facts used for testimony and on principles and procedures used to guide expert opinion. In Pakistan, section 510 (CrPC 1898) deals with the admissibility of DNA reports in criminal proceedings. According to this section, the DNA report is per se admissible and there is prima facie no need to examine the expert on voir dire. Nothing is mentioned in this section related to the qualifications, education or experience of the expert, or the reliability and credibility of the method used to generate a DNA report. Amid the non-uniform standards of analysis in forensic facilities, the courts in Pakistan are unclear about the criteria regarding the technical issues associated with the admissibility of DNA evidence.

DNA databases

Two different kinds of databases are established and used in forensic DNA analysis. One is a population database containing allele frequencies of random unrelated individuals, while the other is an intelligence database. The population database is used to estimate the weight of DNA evidence based upon frequencies of allele prevalent in a particular population, while a DNA intelligence database is used to solve a crime by identifying suspects and linking crimes and criminals with each other. ³⁶ In Pakistan various subpopulation structures living across the country have a distinctive genetic makeup. No local population database containing allelic frequencies of these subpopulations has yet been developed for use in forensic casework and relationship testing. There are three laboratories – the Punjab Forensic Science Agency, Sindh Forensic DNA and Serology Laboratory, and Liaqat University of Medical and Health Sciences – which are routinely doing forensic casework and relatedness testing for judicial proceedings.^37–39 These laboratories use allele frequencies of Asian populations from the NIST database. ⁴⁰ Additionally, the sample size for calculating allele frequencies for the Asian population in STRBase is not very large. As a result of all these factors, a correction factor θ with value 0.03 is used for statistical calculations.^21,41,42 These allele frequencies can be used for casework samples, however serious issues may arise in determining paternity and relatedness for the local population.

The primary objective of the forensic DNA intelligence database is to help police in the identification of the person who was present at a crime scene. The DNA profile obtained from crime scene samples can help to link different crimes with each other and with the perpetrator. ⁴³ Such DNA databases have been established in different countries at a national level and serve as a vital tool for law enforcement agencies, assisting in the prevention and detection of crime, and the effective prosecution and conviction of offenders.^44,45 In Pakistan, no well-managed DNA intelligence database has been developed to help law enforcement agencies and prosecution. The functional laboratories have made their own repositories of in-house-generated DNA profiles of accused, arrestees, victims, elimination samples (victim’s husband, family members of a house, crime scene officers) and profiles generated for paternity and relatedness in civil matters. At the national level, no consolidated DNA intelligence database is available, for optimum use of DNA technology and to reduce the cost of analysis. Moreover, the prevailing legislation is inadequate for the development of any intelligence DNA database in Pakistan.

Conclusion

As in other countries, sex crimes are common in Pakistan, affecting the lives of hundreds of victims per annum. The use of modern technology – that is, forensic DNA analysis – is a vital tool to curb such crimes. In the past few years several serial rapist and killers of children were caught by conducting mass DNA tests in Pakistan. Despite their utility, the biological evidence is prone to various threats, starting from collection to utilisation during the trial in a court. The faulty packaging of evidence material sometimes destroys it before analysis. At the national level, there are no regulations to ensure that forensic facilities avoid errors and perform uniform and quality analyses. Without proper quality control measures, it is highly unlike that we will get the maximum advantage of biological evidence in sexual assault cases. The DNA report predominantly influences the investigation, leading to convictions or the exoneration of accused people in cases of carnal abuse. In the famous Zainab rape and murder case, the DNA profiles of more than a thousand males dwelling in the vicinity were generated, and the perpetrator, named Imran Ali, was identified based on matching his DNA profile with the profile obtained from vaginal swabs of the victim. The suspect was convicted, sentenced to the death penalty by the trial court and sustained by the apex court, then finally executed in 2019. In 2020, an act named as Zainab Alert Bill was enacted by the parliament of Pakistan to cover sex crimes against minors/children. This bill ensures speedy investigation, proper medical examination and compulsory forensic DNA analysis of evidence with the limitation of a period of two months to decide the case in court. According to this Bill, sexual violence against a child would be penalised by death or imprisonment for life. The enactment of new laws and amendments in existing laws dealing with DNA evidence in sexual assault cases is encouraging successful prosecutions in establishing a case, especially where no other evidence (i.e. witnesses) is available. Despite the growing utility of DNA evidence in judicial proceedings, a good number of lawyers and judicial officers have little knowledge regarding the technology behind DNA analysis. There are a few skilled and learned defence lawyers available in Pakistan with the ability to examine the DNA evidence efficiently on voir dire to analyse its relevancy and credibility. Without an allele frequency database of the local population there is a threat to justice due to erroneous statistical calculations, resulting in overemphasis on the DNA evidence. The absence of a proper intelligence database is also another important issue that needs to be addressed immediately to ensure the optimum use of DNA technology. The establishment of more forensic facilities is required to avoid backlogs from existing DNA laboratories and help with the proper treatment of cases in courts. There should be an authority at the national level, responsible for making standards and guidelines for forensic laboratories, to ensure the uniformity and validity of forensic analysis across the country.