A presumption is a reasoning process whereby to some degree, proof of one fact (including the proven absence of a fact) is taken as evidence of another fact. For example, A is an adult, so it is presumed that A is legally competent.
There is a common law presumption of doli incapax, presuming children under the age of 14 are incapable of being criminally liable. This presumption is affirmed within the Youth Criminal Justice Act.
Evidence to the Contrary
Anywhere in the Criminal Code which directs a factual inference unless there is "any evidence to the contrary" (ETTC), is a mandatory presumption.
For example under s. 354(2), an obliterated serial number of a vehicle directs the inference of knowledge that the item was stolen. Where there is no evidence presented to the contrary, the court has no discretion and must conclude knowledge.
Evidence to the contrary "is evidence which is not rejected and which raises a reasonable doubt as to the existence of the presumed fact." However, any evidence that is rejected or disbelieved is not ETTC.
The judge should look at ETTC not as evidence that must be accepted but only as evidence that is capable of raising a doubt.
There is not persuasive or ultimate burden created by the ETTC standard on a balance of probabilities.
Accepted evidence that shows an absence of intent on an essential element for impaired driving, is ETTC.
These code provisions will tend to violate s. 11(b) Charter rights by shifting the burden onto the accused. However, can remain in force under s.1 as a reasonable limitation.
Effect of Satisfying ETTC
Where the accused establishes ETTC, the burden then is upon the prosecution to prove the element beyond a reasonable doubt.
Offences with an ETTC Provision
The phrase "evidence to the contrary" is present in several offences:
- Impaired Driving, Over 80 and Refusal (Offence)
- Failure to Stop or Remain at Scene of Accident (Offence)
- Break and Enter (Offence)
- Unlawfully in a Dwelling (Offence)
- Theft (Offence)
- Possession of a Restricted or Prohibited Firearm (Offence)
- Breach of Undertaking, Recognizance, or Probation (Offence)
- Failing to Provide the Necessities of Life (Offence)
- Agree or Arrange a Sexual Offence Against Child (Offence)
- R v Boyle, 1983 CanLII 1804 (ON CA), (1983), 5 CCC (3d) 193 (Ont. C.A.)
- R v Boyle
R v Proudlock, 1978 CanLII 15 (SCC),  1 S.C.R. 525 at p. 30
R v Nolet (Charette) (1980), 4 M.V.R. 265 at p. 269, per Martin JA
R v Clarke, 2003 ABPC 26 (CanLII), at para 17
R v Tallon, 1992 ABCA 322 (CanLII), (1992) 135 A.R. 146
R v Heisler, supra
Clarke at para 17
R v Proudlock  1 SCR 525, 1978 CanLII 15 (SCC) per Pigeon, J. at page 28
R v Dubois, 1990 CanLII 2776 (QC CA), (1990) 62 CCC (3d) 90 per Fish, J.A. at page 92
R v Gibson, 1992 CanLII 2750 (SK CA), (1992) 72 CCC (3d) 28 per Bayda, C.J.S. at page 38
R v Heisler, (1995) M.V.R. (3d) 305(*no link) per curiam at page 307
R v Oldhauser, (1998) A.J. No. 1323(*no link) per Berger, J.A. at paras 3 and 6
Nolet, supra at p. 269
R v Campbell (1974), 17 C.C.C. (2d) 320 (Ont. C.A.)
- e.g. R v Downey, 1992 CanLII 109 (SCC),  2 SCR 10
see also Fines
Where a presumption places a reverse onus upon the defence, the burden must always be on a balance of probabilities.
Constitutionality of a Reverse Onus Presumption
A reverse onus is invalid where the presumption (generally statutory) establishes a fact that is not reasonable inferred from the proven facts. However, it may still stand where it is justified under s. 1 of the Charter.
Reverse Onuses that have been upheld:
- presumption of knowledge when in possession of stolen property
R v Tupper, 1967 CanLII 14 (SCC),  SCR 589
R v Appleby, 1971 CanLII 4 (SCC),  SCR 303
- R v Oakes, 1983 CanLII 1850 (ON CA), (1983) 2 CCC (3d) 339 (ONCA)
- See Constitutional Challenges to Legislation
- R v Russell (1983), 4 CCC (3d) 460 (NSCA)(*no link) - presumption does not violate s. 11(d)
Common Law Presumptions
A person who possesses stolen property is presumed to have knowledge of its source.
A person impaired by drugs is presumed to be voluntarily impaired unless evidence establishes otherwise.
There is no legal presumption that those testifying in criminal trials are telling the truth.
Presumption of Regularity
The presumption of regularity (omnia presumuntur rite esse acta) in the legal doctrine that creates a presumption that bypasses proof regarding the accuracy and creation of documents and the correctness of actions of public officials.
The presumption of regularity states that a person who acts in a public role is presumed to be entitled to do so. It also creates a rebuttable presumption that official documents, including court documents or public records, are accurate
For the presumption of regularity to be invoked there should exist the following:
- the matter is more or less in the past, and incapable of easily procured evidence;
- it involves a mere formality, or detail of required procedure, in the routine of a litigation or of a public officer's action;
- it involves to some extent the security of apparently vested rights, so that the presumption will serve to prevent an unwholesome uncertainty;
- that the circumstances of the particular case add some element of probability.
The presumption applies to the endorsements on an information.
- Presumption of Sanity - s. 16(4)
- Making Sexually Explicit Materials Available to a Child - s. 171.1(3)
- Child Luring (Offence) - s. 172.1(3)
- Agreement to Commit a Sexual Offence Against a Child - s. 172.2(3)
- Procuring - s. 212(3)
- Necessities of Life - s. 215(4) presumption
- Defamatory Libel (Offence) - s.303 creates presumption that the owner of a newspaper is responsible for any defamatory materials in the publication
- Break and Enter (Offence) - s.348(2) creates presumption that evidence of break-in/break-out is for unlawful purpose
- Unlawfully in a Dwelling (Offence) - s. 349(2) creates presumption of unlawful purpose when found in dwelling
- Obtaining Property by False Pretences (Offence) - s. 362(4) presumption of false pretenses when cheque issued with no funds
- Possession of Stolen Minerals - s. 656 Possession of minerals presumes it was stolen or unlawfully possessed
Presumption of Innocence
At common law, all prosecutions start with a presumption of the accused's innocence. 
Under section 11 of the Charter:
Any person charged with an offence has the right
- (d) to be presumed innocent until proven guilty according to law in a fair and public hearing by an independent and impartial tribunal;
The purpose of the presumption is to protect liberty and human dignity of the accused.
Section 6 of the Criminal Code states:
Presumption of innocence
6. (1) Where an enactment creates an offence and authorizes a punishment to be imposed in respect of that offence,
- (a) a person shall be deemed not to be guilty of the offence until he is convicted or discharged under section 730 of the offence; and
- (b) a person who is convicted or discharged under section 730 of the offence is not liable to any punishment in respect thereof other than the punishment prescribed by this Act or by the enactment that creates the offence.
R.S., 1985, c. C-46, s. 6; R.S., 1985, c. 27 (1st Supp.), s. 4, c. 1 (4th Supp.), s. 18(F); 1995, c. 22, s. 10.
Consideration of whether a statutory presumption is constitutional should include consideration of whether:
- importance of the legislative objective,
- how difficult it would be for the prosecution to prove the substituted fact beyond a reasonable doubt,
- whether it is possible, and how easy it is, for the accused to rebut the presumption, and,
- scientific advances
- Constitutional Challenges to Legislation - statutory presumptions may be invalid due to violating the presumption of innocence.