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what is continuity?

Many criminal investigations involve the collection of evidence. Whenever evidence is collected, it is important for the police to carefully and properly maintain it for the purpose of possible introduction at a trial.  

For example, in a drug trafficking case the police will usually seize drugs and other items (such as identification documents, cellular telephones and weapons). In a break and enter or homicide case, the police might collect forensic evidence such as fingerprints or biological material (DNA). Some impaired driving cases result in the seizure of blood samples.  Many criminal prosecutions rely on forensic technological analysis from electronic devices, such as cellular telephones, tablets and computers.  Many prosecutions rely heavily upon the evidence collected and may rise or fall on both the admissibility of the evidence and the weight to be attached to it. 

Admissibility and weight are separate questions. Admissibility concerns whether an exhibit (such as drugs) is evidence in the trial that can be considered by the trier of fact. Weight, however, essentially concerns the value of admissible evidence in determining whether the prosecution has proven its case "beyond a reasonable doubt".  Sometimes there is a very close and perhaps even confused relationship between admissibility and weight. 

"Continuity" of evidence can be thought in two ways: 

  1. The preservation of evidence.
  2. The chain of custody of evidence.

continuity of evidence: the general rule

In criminal law, the general rule is that the continuity of an exhibit goes to "weight", not "admissibility" (see Nova Scotia v. R.S., [2012] N.S.J. NO. 134 (N.S.C.A.)).   The caveat "general rule" means that there may be continuity related issues that trigger admissibility considerations. For example, in R. v. Penny, [2002] N.J. 70 (N.F.C.A.) the trial judge had legitimate concerns about whether the videotape evidence had been falsified. In this, there was an overlap between whether the evidence had been subject to improper preservation to the point of falsification. In these circumstances, the Court exercised its gatekeeper role to exclude evidence that was more prejudicial than probative. Penny highlights that though continuity is usually a weight issue, the rule is not hard-and-fast.  

When evidence is collected, it is important that it is properly preserved. Put another way, for evidence to have weight, the trier of fact should be satisfied that the evidence is the same (or some cases, substantially the same) as its condition at the time of the commission of the offence. The concept of "sameness" can effect "weight". For example, if a blood sample has been cross-contaminated with other biological material, the similarity between the sample at the time of the offence with the contaminated sample may be so different that the evidence cannot be given any weight. On the other hand, the fact that an exhibit (such a firearm) may have been moved in a crime scene a short distance may lessen the weight, but still not render it valueless at trial. 

crime scene spoof illustrative

This crime scene spoof illustrates preservation issues:


 The moment Samuel L. Jackson enters the home it is apparent that police are trampling the crime scene.  Jackson's first question, "what you got Herb"?  Herb's response, while scratching his head, "beats me Sarg. Dandruff, dry itch and scale?".  Of course Herb is potentially contaminating the crime scene with his own skins cells and hair follicles. The next scene shows Jackson walking into a room with a body. A police officer puts up police tape labelled "caution wet blood".  What is noticeable is that nobody at the scene is taking care with respect to entering the area where blood evidence may be found.  Also, no police officers are wearing protective gear designed to contain their own biological material.

This spoof can be broken down throughout. Of course, real police are usually much more careful.  

Properly preserving the crime scene means that it should be left, where at all possible, undisturbed. In this spoof, there are police trampling the scene, thus creating disturbances.  Those disturbances, however, may not impact (or significantly) the weight of the evidence to be collected if for example they did not trample a specific area of investigation (such as where the forensic examiner is leaning over the body).

Once evidence is collected it is important for the police to maintain a chain of custody. In that chain, evidence should be properly stored to ensure that it is preserved. 

For example, in an impaired driving case where police seize blood, it is important that they follow blood from the moment it is collected from the person to the moment when it is seized by them. Once seized, that blood needs be properly stored to ensure that its integrity is maintained. The blood might be transferred from a storage receptacle (such as a refrigerator) to a blood analyst. The chain of custody should be followed to that analyst and when the blood is analyzed, proper procedures should be adhered to.  If the blood analyst fails to clean his or her work station that could result in the contamination of a blood sample. 

Where there has been a loss of continuity -- or break in the chain of custody -- a court may develop concerns about the reliability of the evidence.  If the break in the chain of custody is significant, a court may place little or no weight on the evidence.

retain a qualified calgary defence lawyer

It is not unusual for defence counsel to admit continuity of exhibits at trial. The reason this occurs is because there are often no continuity issues identified in the disclosure.  In such cases, the admission of the evidence is to ensure trial efficiency and to focus the issues for attention by the Court. 

Whether continuity is an issue at a trial requires assessment by an experienced and qualified criminal defence lawyer. David Chow is a Calgary defence lawyer who has successfully defended serious cases of drug trafficking, home invasion and other crimes based on continuity issues.  Call 403.452.8018 for a free telephone consultation. 

Do your due diligence.  There are proven and experienced Calgary criminal lawyers who can help. David Chow is one of them.

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