Obtaining and Banking DNA Forensic Evidence

Response by the Office of the Privacy Commissioner of Canada to the Department of Justice's consultation paper

January 1995


Forensic DNA analysis can be a powerful tool for linking genetic samples from the scene of a crime or from the victim (semen, for example) with a suspect. It can also completely exonerate a suspect. However, the intrusiveness of this technique necessitates careful regulation of the circumstances in which a criminal suspect or convicted offender should be required to supply DNA.

We applaud the Department of Justice for raising the privacy implications of forensic DNA analysis in its consultation paper. Our response expands on the privacy issues raised in the consultation paper and identifies specific privacy protections that should be included in legislation. It discusses how the code of fair information practices set out in the Privacy Act should be incorporated in any law that permits the taking of DNA. It also discusses how such a DNA analysis law can respect broader notions of privacy.

Specifying a Code of Fair Information Practices Within the DNA Testing Law

The Privacy Act sets minimum standards of fair information practices. These standards govern the collection, use and disclosure of personal information by federal government institutions and provide rights of access to the personal information they hold. (Section 3 of the Act defines personal information in part as information about an identifiable individual that is recorded in any form.) The standards apply to most federal government institutions, including the RCMP.

Incorporating fair information practices in a single federal law governing DNA sampling will provide consistency in the law across Canada. The law should apply to municipal and provincial police forces as well as the RCMP.

However, they do not cover non-federal police forces. Other police forces may be covered by provincial privacy laws that are broadly similar to the federal Privacy Act, but the nature of that coverage may differ from that of the federal act.

Incorporating fair information practices in a single federal law governing DNA sampling will provide consistency in the law across Canada. The law should apply to municipal and provincial police forces as well as the RCMP.

Any DNA analysis law should at a minimum mirror, and preferably, expand, the code of fair information practices set out in the Privacy Act. The code in the Privacy Act sets the following standards:

  • collecting information, in this case, via a DNA sample, directly from the individual concerned unless the person authorizes otherwise or where the personal information may be disclosed to the institution under subsection 8(2), the main disclosure provision of the Act (subsection 5(1))
  • informing the individual from whom the sample is taken of the purpose of the collection (subsection 5(2))
  • retaining the information for an appropriate period after it has been used, to allow the individual to whom it relates a reasonable chance to obtain access to the information (subsection 6(1)); this would apply to information from the crime scene and from the suspect
  • taking all reasonable steps to ensure that the information generated by the DNA analysis and used for an administrative purpose (for example, a prosecution) is as accurate, up-to-date and complete as possible (subsection 6(2))
  • disposing of the information in accordance with regulations and any directives or guidelines issued by the designated Minister (subsection 6(3))
  • disclosing the information without consent only as permitted by the Act (subsection 8(2))
  • allowing access to personal information contained in a personal information bank, unless the head of a government institution refuses access under section 22 of the Act (section 12).

Clearly, some standards set out in the Privacy Act would not meet the basic requirements for a fair criminal trial. For example, disclosure in criminal trials is less restricted than under section 22 of the Act. Thus, the drafters of any law permitting DNA analysis should view the Privacy Act as setting out only minimum standards.

Below, we suggest specific additional fair information practices that should be incorporated into any DNA analysis law.

1. Taking the sample

A person from whom a genetic sample is taken without consent will view this action as a violation of his or her physical integrity. This is so even if the law allows the forced taking of the sample.

Whatever type of genetic sample is collected:

  • blood
  • hair or
  • scrapings from the inside of the mouth

    the sample should be collected by a health care professional such as:

    • a physician
    • a nurse
    • or qualified medical technician.

Taking the sample will still be intrusive, but this would be partly mitigated by using competent health care professionals.

2. Which genetic material to take

Parliament should require using the least intrusive collection method consistent with good forensic practice. There is no point in using the least intrusive means to take a genetic sample if this method does not give a reliable DNA sample.

There may be some debate about which type of collection is the least intrusive, an oral scraping or taking hair, for example. Taking blood, likely with a finger lancet, might be considered the most intrusive form of sample gathering, but it may be justified if it provides the most reliable way to obtain a DNA sample.

The suspect or convicted offender should be allowed to specify the method of sampling as long as that method produces a reliable sample.

3. Collecting DNA from suspects

DNA evidence should not be collected from a suspect unless the information is relevant to a specific crime in question. For example, it would be appropriate to obtain a DNA sample from a suspect where DNA evidence is left at the scene of the crime and the suspect's DNA is needed to prove the suspect's involvement.

DNA evidence should not be collected from suspects as a matter of routine. To do so cause an unnecessary privacy intrusion; in the vast majority of criminal cases DNA evidence will contribute nothing to the investigation. Thus, it would not be appropriate for Parliament to give blanket authority to collect DNA samples from all persons suspected of indictable offences. DNA should also not be collected from a suspect if investigators have no DNA evidence with which to compare the suspect's sample.

Nor would a DNA sample from the suspect be necessary if the suspect admitted guilt.

However, as a practical matter, the DNA evidence might be critically important in getting the suspect to admit guilt in the first place.

As well, there should be reasonable grounds for suspecting that the person committed the offence before taking the DNA sample. It would not be acceptable to require all men in a given community to submit DNA samples to solve a specific crime.

Broadly-based testing of whole groups within a community would represent an unjustifiable intrusion into the lives of too many innocent people. As a further privacy safeguard, DNA evidence should be collected from a suspect only if a judge authorizes the collection.

In our 1992 report, Genetic Testing and Privacy, we discussed limiting the collection of DNA samples to cases involving criminal violence. The types of violence crimes for which DNA samples might be collected should be set out in legislation. The list of violent crimes set out in New Zealand's recently introduced Criminal Investigations (Blood Samples) Bill offers an example of the types of crimes for which DNA testing might be considered in Canada. The New Zealand list is attached as an appendix. It may also be appropriate to allow the collection of samples for other crimes, such as conspiracies to commit offences involving violence. For example, it should be lawful for samples to be taken if DNA evidence could help convict someone suspected of planning a terrorist act or murder (perhaps the suspect had left DNA on a stamp he licked and attached to a letter implicated in the crime).

In short, we recommend the following conditions on the collection of DNA samples from suspects:

  • the crime must involve violence or the likelihood of violence
  • there must be reasonable grounds for suspecting that the person committed the offence
  • a DNA sample must be relevant to proving the offence; investigators must have DNA related to the crime with which the suspect's sample can be compared, and
  • the collection from the suspect must be authorized by a judge.

4. Sample to confirm or negate a match only

The analysis of the samples should be used only to confirm or negate a match between the sample taken from the crime scene and the sample taken from the suspect. That is, it should remain an identification tool only. There should be no further analysis of the DNA to suggest psychological characteristics that would make the suspect more likely to have committed the crime. This rule should also apply to samples taken from convicted offenders for a database or databank.

5. Collecting or retaining DNA from convicted offenders

We have argued that DNA samples should not be taken routinely from suspects. Similarly, DNA samples should not be taken routinely from convicted persons.

Any proposed DNA analysis law should permit DNA samples to be taken from a convicted offender only when the offender has been convicted of a violent offence (or conspiracy to commit a violent offence) identified in the legislation authorizing testing.

Another factor in deciding whether to take a sample would be the likelihood of the convicted offender committing another violent offence where DNA evidence might be left at the scene. Even conviction of an offence such as murder might not automatically justify taking a DNA sample from the offender, given the very small likelihood of recidivism.

In some cases, of course, authorities would already have a DNA sample taken from the offender at the time of his or her trial. Unless there is a valid scientific justification for doing so, the state should not require the convicted offender to give a second sample.

DNA database vs. DNA databank: There is debate about whether the actual sample given by the convicted offender should be retained. The alternative is to keep only the analysis of the sample in a computer database.

Maintaining the actual sample will inevitably invite testing beyond looking for the identifying information available through forensic DNA analysis. Scientific curiosity and public pressure to reduce crime will almost certainly lead to interest in using samples of convicted offenders to look for common genetic traits that may be linked to anti-social behaviour. This type of research, while perhaps of scientific interest, raises enormous ethical problems with which society may not yet be prepared to deal. Society may also be too willing, as happened with the XYY chromosome experience in the late 1960s and early 70s, to rely on preliminary and tentative evidence of genetic links to crime as if they were well-established fact. This could lead to the unwarranted labelling and mistreatment of individuals, and their law-abiding biological relatives, as deviant because of their genetic makeup.

Above all, this additional testing would represent a substantial further privacy intrusion that may not be justified by the possible benefits from acquiring further knowledge. Our strong preference is for the retention of the identification analysis only of the DNA samples, not the samples themselves. This may cause some additional expense and require resampling of convicted persons as forensic DNA analysis techniques change. However, retaining actual DNA samples from convicted offenders requires the strongest possible justification. Administrative convenience and reduced expense are not sufficient.

6. Disposal of DNA sample from suspect of accused

In some situations, the DNA sample taken from the suspect or accused (and any analysis of that sample) should be destroyed, for example, if the Crown does not proceed with a charge for the incident for which the sample was taken, if the Crown withdraws the charge or enters a stay, or if the accused is acquitted. The sample should not be retained in a bank of genetic samples, nor should the analysis be retained in a DNA database. A database should be retained for certain convicted offenders only.

7. Use of DNA analysis before conviction to solve other crimes

One difficult issue is whether a sample taken from a suspect in one crime, a person who may even have been charged, should be available for trying to solve other crimes. We recommend prohibiting the use of the sample for other cases until the suspect is convicted of the first crime, unless the Crown can persuade a judge that the suspect may have been responsible for those other crimes.

In other words, until the person is convicted, a DNA sample should be used only to compare with the sample from a crime for which the person is a suspect. The taking of the sample and its use to resolve any unsolved crime would therefore require a judge's approval; this would be granted only if the Crown could establish reason to suspect that the individual may have committed that other crime.

After conviction, DNA information could be used, without a court order, to seek a connection with any unsolved crime of a similar nature. For example, genetic information from the DNA of someone convicted of a sexual assault could be used to look for a match with unsolved sexual assaults. Use of the information generated by the DNA to resolve crimes that are not of the same nature as the one for which the person was convicted, should require a judge's approval. This would prevent a fishing expedition.

8. The cost of challenging DNA analysis

The state should assume the cost of DNA testing done for the defence to ensure that lack of money does not prevent the accused from challenging the accuracy of sophisticated and expensive scientific analyses. Financial help should extend to allowing the suspect (who by now has likely been charged and is therefore an accused) be able to challenge the analysis of the analysis of the sample taken from the crime scene and the sample taken from him or her.

9. Accuracy of information

The Privacy Act requires that information retained by a government institution be as accurate as possible. Analysis techniques should therefore be done under the most rigorous scientific conditions, and forensic analysis techniques should be reviewed periodically to ensure their accuracy

Criminal Investigations (blood samples)

Article 2



Disposition of the Crimes Act of 1961

  • Sexual violation (article 128)
  • Attempt tocommit sexual violation (article 129)
  • Inducing sexual connection by coercion ( article 129A)
  • Incest (article 130)
  • Sexual intercourse with girl under care or protection (article 131)
  • Sexual intercourse with girl under 12 ( paragraphe 132(1))
  • Attempted sexual intercourse with girl under 12 ( paragraphe 132(2))
  • Indecency with girl under 12 (article 133)
  • Sexual intercourse with girl between 12 and 16 (paragraphe 134(1))
  • Indecency with girl between 12 and 16 (article 134(2))
  • Sexual assault on woman or girl (article 135)
  • Sexual intercourse with severely subnormal woman or girl (article 138)
  • Indecency with boy under 12 (article 140)
  • Indecency with boy between 12 and 16 (article 140A)
  • Indecent assault on man or boy (article 141)
  • Anal intercourse (article 142)
  • Murder (articles 167, 168)
  • Manslaughter ( article 171)
  • Attempt to murder (article 173)
  • Wounding with intent to cause bodily harm (paragraphe 188(1))
  • Wounding with intent to injure (paragraphe 188(2))
  • Injuring with intent to cause grievous bodily harm (paragraphe 189(1))
  • Aggravated wounding (paragraphe 191(1))
  • Aggravated injury ( paragraphe 191(2))
  • Infecting with disease ( article 201)
  • Abduction of woman or girl (article 208)
  • Kidnapping (article 209)
  • Robbery (article 234)
  • Aggravated Robbery ( article 235)
  • Aggravated burglary (article 240A)
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