Clinical focus: Medical evidence in Sexual and Gender-Based Violence (SGBV) is collected during compassionate clinical care—not as an interrogation. Evidence can support health decisions and legal processes, but no single finding proves or disproves assault, consent or identity. Follow current Ugandan Ministry of Health, police, child-protection and laboratory procedures for kits, reporting and retention.
Learning objectives
- Explain the purpose, limits and consent requirements of medical-forensic evidence.
- Take a focused, trauma-informed history and conduct a complete, respectful examination.
- Collect, label, package, store and transfer biological and non-biological evidence correctly.
- Document injuries and normal findings objectively with diagrams, photographs and measurements.
- Interpret DNA, semen, blood, toxicology and injury findings without overstating their significance.
- Protect the survivor’s health, privacy, safety and choices throughout the process.
1. What medical evidence can and cannot answer
| Medical evidence may help to | It generally cannot determine on its own |
|---|---|
| Identify injuries, infection, pregnancy or urgent medical needs. | Whether a person is truthful, whether a crime occurred, or who is legally guilty. |
| Document the survivor’s account and the condition of the body at examination. | Consent from the absence or presence of injury. |
| Recover biological material or foreign material for validated laboratory testing. | The exact time of an assault from a bruise, semen or DNA result alone. |
| Provide an expert opinion about compatibility of findings with a described event. | That a “negative” sample excludes assault, especially after delay, washing, condom use or non-penetrative contact. |
| Guide treatment, follow-up, safeguarding and referrals. | That detection of a drug proves incapacitation or perpetration without dose, timing and context. |
2. Consent and patient-centred preparation
Consent for treatment, forensic examination, photographs, specimen collection, release of records and police contact should be explained separately. Consent must be voluntary, informed, specific and ongoing. A survivor may accept some parts and decline others without losing care.
- Ensure privacy, a chaperone chosen with the survivor, an interpreter who is not involved in the case, and a safe way to communicate.
- Explain the purpose of the examination, what it may involve, possible discomfort, storage and possible release of evidence, and alternatives.
- Ask the survivor to tell you when to pause. Offer breaks, clothing, blankets, water, pain relief and support.
- For children and adults lacking capacity, follow Ugandan law and safeguarding policy regarding assent, legally authorised permission and mandatory reporting.
- Document consent, refusals, pauses, who was present, the information provided and any limits.
Emergency exception: Life-saving care should not wait for forensic consent. Treat airway injury, bleeding, poisoning, shock, head injury, strangulation or suicide risk immediately, then revisit evidence options when the patient is stable.
3. Before evidence collection: history and contamination control
Focused history
Use open questions first and record the survivor’s words. Clarify the time, location, acts, sites of contact, use of barrier protection, ejaculation, bleeding, pain, urination, washing, changing clothes, eating/drinking, oral or anal exposure, loss of consciousness, drugs/alcohol, threats, weapons and previous consensual intercourse. Explain that these questions guide medical care and sample selection; they are not a test of credibility.
Contamination control
- Use clean gloves and change them between body areas or specimens. Avoid touching swabs or the inside of containers.
- Use sterile, individually packaged equipment and a clean examination surface. Keep known reference samples separate.
- Collect clothing and debris in paper bags when dry; do not seal wet biological material in plastic. Air-dry according to protocol.
- Do not wash, brush, cut hair or remove foreign material before sampling unless clinically necessary; if the patient already did so, document it without blame.
- Use a new instrument for each swab/site. Label at collection, not later.
4. General medical assessment
- Stabilisation: ABC, vital signs, glucose where indicated, mental status, pain, bleeding, pregnancy possibility, head/neck injury and strangulation red flags.
- Whole-body examination: inspect scalp, face, mouth, neck, torso, limbs, hands, genital and anal areas as indicated by history and consent.
- Injury description: site, side, anatomical landmark, size, shape, colour, orientation, edge, base, tenderness, swelling, discharge, healing and associated findings.
- Normal findings: document relevant normal skin, oral, genital or anal findings; a normal examination is common and does not exclude violence.
- Clinical tests: pregnancy test, HIV/STI tests, urinalysis, imaging, blood count, renal/liver tests and toxicology according to exposure, symptoms and local protocol.
5. Evidence categories
| Category | Examples | Collection/interpretation notes |
|---|---|---|
| Biological | Blood, saliva, semen, epithelial cells, hair, urine, vaginal/anal/oral swabs | Collect targeted samples promptly; dry/package correctly; DNA presence does not establish timing, consent or identity without comparison and statistics. |
| Non-biological trace | Fibres, soil, glass, paint, vegetation, lubricants, condoms, foreign material | Use clean instruments and separate packaging; avoid transferring scene material. |
| Clothing and personal items | Underwear, sanitary products, bedding, condoms, torn clothing | Package each item separately in paper; record who supplied it and whether it was washed. |
| Injury evidence | Photographs, diagrams, measurements, imaging, swabs from wounds | Describe, do not label an object or weapon without comparative examination. |
| Toxicology | Blood, urine, hair or vomitus for alcohol/drugs | Timing, specimen type, preservatives and chain of custody are critical; a negative result does not exclude drug-facilitated assault. |
| Digital/contextual | Messages, images, location data, call logs | Do not seize or alter devices outside authority; preserve metadata through trained investigators. |
6. Specimen selection and collection
Use the current local sexual-assault evidence kit and laboratory instructions. The following framework helps students understand why each sample is considered; it is not a substitute for the kit’s validated swab sites or time windows.
| History/examination | Potential specimen | Important limitation |
|---|---|---|
| Oral contact or ejaculation | Oral swabs, oral rinse where protocol allows | Short persistence; eating, drinking and brushing reduce recovery. |
| Vaginal/cervical contact | External, vaginal and/or cervical swabs according to protocol | Normal flora and consensual intercourse can contribute DNA; interpret with history and reference samples. |
| Anal contact | Perianal/anal swabs and injury documentation when indicated | Stool contamination and delayed presentation affect yield. |
| Skin, bite or lick | Swab before cleaning; photograph injury | Touch DNA is easily transferred and may be low quantity. |
| Clothing or bedding | Separate dry paper packaging | Wet plastic packaging promotes degradation and contamination. |
| Possible drug-facilitated assault | Early blood and urine; other specimens only on specialist advice | Many drugs clear quickly; a negative test never excludes incapacitation. |
| Known comparison needed | Reference buccal sample with lawful consent/authority | Label separately; do not mix with questioned samples. |
Collect pregnancy and STI diagnostic samples for care even when forensic samples are declined. Diagnostic specimens and forensic exhibits have different purposes, containers and custody pathways.
7. Chain of custody
Chain of custody is the continuous, chronological record of every person and location associated with an exhibit. It establishes continuity and helps the laboratory and court evaluate integrity.
- Assign a unique case/exhibit number and label patient/specimen, site, date/time and collector.
- Seal each item with tamper-evident material; sign/date across the seal.
- Complete the evidence form at the bedside, including the condition of the seal and any deviations.
- Record every transfer with sender, recipient, date/time, purpose, storage conditions and signatures.
- Store securely with restricted access and transport promptly to the designated laboratory/police evidence unit.
- Report lost, delayed, wet, unsealed, relabelled or contaminated items honestly; do not recreate a chain retrospectively.
8. Documentation and photography
Written record
- Record the date/time, facility, examiner, chaperone, interpreter, referral source and consent.
- Separate sections for history (with quotes), examination, specimens, investigations, treatment, referrals and opinion.
- Use anatomical landmarks, side, size in millimetres/centimetres, shape, colour, orientation and diagrams. Describe “linear, 3 cm, purple-red, tender bruise over the right upper arm,” not “bad bruise.”
- Document negative findings relevant to the history, the patient’s words, actions already taken (washing, urination, clothing change) and any delays.
- State limitations: time elapsed, healing, incomplete examination, declined samples, uncertain history, test sensitivity or contamination.
Photographs
Obtain separate consent. Use a scale for close images, an identification label without unnecessary personal information, overall and close views, consistent lighting and secure storage. Do not send images through personal messaging apps or store them on an unencrypted phone. Record who took them, when, what they show, where they are stored and who can access them.
9. Interpreting common evidence
| Finding | What it may indicate | What it does not prove |
|---|---|---|
| Semen/sperm or semen marker | Possible seminal material at a sampled site. | Who deposited it, when, or whether the act was consensual. |
| Foreign DNA | Biological material from a contributor may be present. | Timing, route of transfer, assault or absence of consensual contact. |
| Genital/anal injury | Trauma, inflammation, infection or another condition may be present. | That penetration occurred, who caused it or exact timing without context. |
| No injury | No visible injury at that examination. | That no assault occurred; mucosa may heal rapidly and many assaults cause no injury. |
| Positive STI or pregnancy test | Infection or pregnancy is present and requires care. | Who transmitted it or when the assault occurred; infection may predate exposure. |
| Alcohol/drug detected | A substance or metabolite is present at a measured concentration. | Impairment, inability to consent, dose, source or perpetrator without clinical/toxicological context. |
| Bruising/abrasion | Blunt/friction trauma is possible. | Exact age, object, mechanism or perpetrator; colour cannot date a bruise reliably. |
10. Toxicology and drug-facilitated assault
Ask what was consumed, when, with whom and whether the survivor had memory gaps, unexpected sedation, weakness or vomiting. Obtain consent and collect the earliest feasible specimens through the designated toxicology pathway. Record prescribed medicines, recreational substances and medical conditions that influence interpretation. A negative result can occur after delay, small dose, rapid metabolism, incomplete panel, storage error or prior urination.
Do not promise that toxicology will identify a perpetrator or “prove” incapacitation. Protect clinical care: manage airway, breathing, hypoglycaemia, seizures, temperature, trauma and withdrawal risk first.
11. Children and adolescents
- Follow child-protection law and a specialist pathway. Do not make a child repeat the story to multiple clinicians.
- Use simple, non-leading questions; record exact words and behaviour. A normal genital examination is common and does not exclude abuse.
- Obtain age-appropriate assent and lawful permission; explain mandatory reporting limits before disclosure where possible.
- Consider pregnancy, STI/HIV, injuries, grooming, trafficking, online exploitation, immediate safety and caregiver risk.
- Do not collect invasive samples beyond training and protocol; paediatric forensic examination requires specialised skills.
12. When evidence is declined or presentation is delayed
Respect the decision and continue treatment, documentation, safety planning and referral. Evidence collection is not the gate to care. Delayed presentation does not make care futile: injuries, pregnancy, infection, mental-health needs, safeguarding and some biological/trace evidence may still be relevant. Record time elapsed, actions already taken and which options were offered or declined.
13. Clinical and ethical quality assurance
| Risk | Prevention |
|---|---|
| Retraumatisation | One trained examiner where possible, explain each step, allow pauses, avoid repeated narratives. |
| Contamination | Clean equipment, separate packaging, gloves changed between sites and dry paper for biological items. |
| Misinterpretation | Use validated tests, state limitations, obtain reference samples lawfully and use qualified laboratories. |
| Loss of confidentiality | Private rooms, minimum-necessary disclosure, secure records and safe telephone follow-up. |
| Chain break | Label at collection, tamper-evident seals, complete every transfer and report deviations. |
| Conflict of roles | Separate care from investigation where possible; remain independent and document objectively. |
14. Worked cases
Case 1: Late presentation after washing
A survivor presents 72 hours after an assault, has showered and changed clothes, and has no visible injury. Provide LIVES support, injury and mental-health assessment, pregnancy/STI/HIV care, and explain forensic options without implying that washing ruined the case. Document the history and the normal findings; collect only samples justified by the current history and local protocol.
Case 2: Positive DNA on underwear
A DNA profile from underwear matches a partner. The result supports the presence of biological material but cannot independently establish timing, assault or lack of consent. The report should state the analytical method, reference sample, likelihood ratio and limitations.
Case 3: Possible drug-facilitated assault
A survivor reports sudden amnesia and sedation after one drink. Stabilise and assess for poisoning, collect early blood/urine through toxicology protocol, record all medicines and substances, and explain that a negative test does not exclude exposure.
15. Quick self-test
- What are the separate consents that should be considered in a medical-forensic examination?
- Why should wet biological evidence usually not be sealed in plastic?
- Does a normal genital examination exclude sexual assault?
- What does chain of custody document?
- What is the appropriate wording when a finding could have several causes?
Answers
- Consent for treatment, examination, photographs, specimen collection, storage/release and police/legal contact may need separate explanation and agreement.
- Moisture encourages bacterial/fungal degradation and can compromise DNA or other testing.
- No. Many assaults cause no visible injury, and healing or delayed presentation affects findings.
- Identity, collection, seals, storage, transfers, dates/times, handlers, purpose and integrity of each exhibit.
- Use neutral wording such as “consistent with” or “compatible with,” describe alternatives and state limitations; do not claim proof.
Key take-home points
- Medical-forensic evidence supports care and legal investigation but does not by itself determine consent, assault or guilt.
- Consent is specific and ongoing; a survivor may decline any specimen or photograph and still receive full care.
- Collect targeted samples early, prevent contamination, package correctly and maintain an unbroken chain of custody.
- Document both injuries and relevant normal findings objectively, with measurements, diagrams and consented photographs.
- Interpret DNA, semen, injuries, toxicology, pregnancy and STI results with timing, baseline history and laboratory limitations.
- Children, people lacking capacity and survivors in immediate danger require safeguarding and specialist referral.
References and further reading
- WHO: Clinical management of rape and intimate partner violence in emergencies
- WHO: Guidelines for medico-legal care for victims of sexual violence
- WHO: Responding to intimate partner violence and sexual violence
- WHO: Caring for women subjected to violence
- Uganda/WHO-aligned SGBV and violence-against-children trainee manual
Educational note: Use the current Ugandan evidence kit, laboratory requirements, safeguarding policy and legal reporting rules. This post is not legal advice.
