The media reports on the conduct of the medical examination involving PKR leader Anwar Ibrahim is very confusing.

And the clarification by Hospital Kuala Lumpur director Dr Zaininah Mohd Zain ( New Straits Times , July 20) did not help to clear the matter but leave the general public to make their own interpretation which might compromise the credibility of the hospital authority or the accused person.

As a practicing clinician with some experience in examining the rape or sodomy victims or the accused persons in the past and has had to testify as a witness in a number of rape trials, I would like to detail out in my knowledge how the medical examination of the accused person in rape and sodomy cases is carried out according to the standard procedure, which I believe still stands today.

Obtaining consent

The protocol is basically the same as for the victim except that the police will produce the accused. A valid consent is essential before examination in which there should not be any force or duress or fraud while obtaining consent. While the victim may have the choice not to consent for the full examination, the accused is often left no choice but to agree and comply with the order for obvious reasons.

It is the responsibility of the doctor who seeks consent to explain all aspects and the implication of his consent to the person. The doctor should be unbiased as the person produced is only an accused and not proved of the offence and hence could be innocent.

Complete privacy is essential and therefore while interrogating the person, no one should be permitted to be present in the room. The police officer could be politely requested to stay outside the room. A detailed history is obtained from the suspect and it is documented in his own words. During interrogation, his behaviour, mental state, truthfulness of the statement, and evidence of intoxication with drugs or alcohol is observed and recorded.

Physical examination

The examination room should be clean with good lighting. A male nurse or a medical attendant should be present during the examination. The suspect is made to completely undress and a careful examination is carried out from head to toe, front and back for evidence of physical injuries, state of physical development and the presence of physical abnormality.

If the suspect is produced immediately or shortly after the alleged offence, then undressing has to be done while standing on a clean sheet of paper in order to collect any loose trace materials that may still be sticking to the body and clothes. The clothes should be carefully examined for the presence of seminal fluid, blood, mud stains and any tears and the details are recorded with sketches. The cloths and the collecting paper that might have collected foreign materials such as blood, pubic hairs, etc, are then packed into clean paper bags and forwarded to the police to be sent to the analytical laboratory.

The injuries may be present if there had been a struggle. Scratch abrasions caused by finger nails are to be looked for on the face, neck, back of chest, trunk, buttocks and upper limbs. There may be contusions present on the suspect caused by fingertips, pinching, punching or kicking during the struggle.

The colour changes that occur in surface contusions will be useful in making a rough estimation of the age of the injury and this will be helpful in corroborating with the date of the alleged offence. If marks or injuries due to bites are present, the assistance from the forensic odontologist will be sought for, if necessary.

The private part or external genitalia of the accused is carefully examined. The development of the penis, its size (measurement will be taken), circumcised or not, whether the foreskin is retractable, development of the testicles and any other abnormalities are observed and recorded. Evidence of other injuries will be looked for as well.

The foreskin of the penis will be retracted and the frenulum (the bridge at the base of the glans penis) is examined as this is an area that can be injured during violent intercourse. We also look for swelling, tenderness and damage to the glans penis especially towards the rim of the glans penis. The testicles will be palpated for evidence of haematoma, hydrocele or tenderness if there is trauma and evidence of sexually transmitted diseases will be looked for and recorded in detail.

Issue of potency

If an issue is raised as to the potency of the suspect then this matter should be resolved by a thorough clinical examination. Initial examination will reveal whether there are any anatomical abnormalities that contribute to impotence. General clinical examination will exclude any systemic diseases or neurological disorders that contribute to impotence.

A psychiatric assessment of the suspect may become necessary if it is thought that emotional and psychological factors might contribute to the male impotence. Forcing the suspect to ejaculate by masturbation as a proof of potency is certainly unacceptable and unethical. The capability to ejaculate by masturbation does not prove potency and has no bearing in the alleged offense of rape or sodomy.

Collection of specimens

If the case is a fresh case, foreign materials sticking to the body or stains on the skin is collected into a clean envelope or bottle. The pubic area will be combed to locate loose hair, which may be from the victim and this is collected into a clean envelope. About 20 pubic hairs are plucked and collected separately, which may be needed for comparison. Swab is taken from the glans penis to look for the presence of vaginal epithelium in the case of rape or rectal mucosa in the case of sodomy. If necessary, finger nail clippings are obtained to look for tissues or blood belonging to the victim.

Specific precautions have to be taken in collecting, storing and transmitting the specimens to the analytical laboratory or chemistry department. The specimens have to be correctly labeled and forwarded to relevant analytical laboratories by the police without any delay.

Undue delay on the part of the police to deliver the specimens to the laboratory (which many times is the case) may result in the specimens becoming unsuitable for analysis. It is possible to make some arrangements to forward the specimens, provided the continuity of evidence and credibility of the force forwarding the specimen is maintained.

It is important that the doctor should always remain unbiased and his report should be based on the available facts. There is no place for speculation and no conclusion to be drawn from vague or unascertainable facts. It is a legal principle that the benefit of doubt should always be given to the accused.

DR SHARIFAH HALIMAH JAAFAR is senior lecturer and consultant obstetrician and gynaecologist at University Kuala Lumpur Royal College of Medicine Perak.