Obstruction of justice is one of the broadest offences in the Criminal Code, capturing a wide range of conduct aimed at interfering with the justice system itself rather than any specific victim. This guide explains how the offence is defined under section 139, how it differs from the more commonly charged offence of obstructing a peace officer, potential penalties, and possible defences. It is general legal information, not legal advice about a specific case.
What Does This Offence Cover?
Section 139 of the Criminal Code makes it an offence to wilfully attempt, in any manner, to obstruct, pervert, or defeat the course of justice. The provision is deliberately broad and is not limited to a fixed list of conduct, but it commonly captures actions such as dissuading a witness from testifying or from giving information to police through threats, bribes, or other means, fabricating or destroying evidence, coaching a witness to give false testimony, or attempting to influence a juror. A related but narrower provision, section 139(1), specifically addresses obstructing justice in relation to a recognizance, such as attempting to deceive a surety about the risks of the arrangement.
Because the wording of section 139 is open-ended rather than a fixed list, courts have applied it to conduct that did not exist in its current form when the section was first written, including interfering with digital evidence relevant to an investigation, such as deleting text messages or social media content after learning of a police inquiry, or coordinating a false alibi with another person. The common thread across these examples is conduct aimed at corrupting the truth-finding process of a criminal or civil proceeding, rather than any single specific act.
Obstruction of Justice vs. Obstructing a Peace Officer
This offence is frequently confused with the separate and more commonly charged offence of obstructing a peace officer under section 129 of the Criminal Code. Section 129 targets in-the-moment interference with an officer in the lawful execution of their duty, such as physically resisting a lawful arrest, providing a false name to police, or otherwise hindering an investigation at the scene. Section 139, by contrast, targets interference with the administration of justice more broadly, including conduct aimed at witnesses, evidence, or judicial proceedings that may occur well before or after any interaction with police at a scene. The two offences can sometimes arise from the same general set of events, but they are legally distinct, and section 139 carries a significantly higher maximum penalty on indictment.
A separate but related offence, public mischief, addresses knowingly making a false statement that causes a police officer to investigate a crime that did not occur or to suspect an innocent person, such as falsely reporting a theft or fabricating a complaint against someone. While public mischief and obstruction of justice both involve misleading the justice system, they are charged under different sections of the Criminal Code and involve different conduct: public mischief centres on triggering a false investigation, while obstruction of justice more often involves interference with an investigation or proceeding that is already underway.
Classification and Penalties
Obstruction of Justice (Section 139) at a Glance
- Classification
- Hybrid offence (Crown elects summary conviction or indictment)
- Maximum penalty – indictment
- Up to 10 years imprisonment
- Maximum penalty – summary conviction
- Up to 2 years less a day and/or a $5,000 fine
- Mandatory minimum sentence
- None
These figures reflect the Criminal Code as of this page's last update. Actual sentences depend heavily on how the underlying justice process was affected and the seriousness of the proceeding interfered with. A criminal lawyer can confirm the current state of the law for a specific case.
Common Scenarios
Obstruction of justice charges commonly arise from attempting to convince a witness to change or withdraw a statement, offering money or favours in exchange for false or altered testimony, destroying or hiding physical evidence relevant to an investigation or court proceeding, or coaching another person on what to say to police or in court. It can also arise from more indirect conduct, such as pressuring a complainant in a domestic assault matter to recant, which can result in obstruction charges against the person applying the pressure separate from the original offence.
Contacting a witness or complainant in an ongoing case, even with no explicit threat, can create serious legal risk, particularly where a no-contact bail condition already exists. Any concern about a witness's evidence should be raised through a lawyer, not directly with the witness.
Possible Defences
Because the offence requires wilful conduct, a central issue in many cases is whether the Crown can prove the accused intended to interfere with the course of justice, or knew that the conduct would likely have that effect, as opposed to conduct that was careless, ambiguous, or had an entirely different purpose. Other issues can include whether the conduct actually had a real tendency to obstruct, pervert, or defeat a specific justice process, since the offence is not made out simply because conduct is later characterized as suspicious. A criminal lawyer should review the specific conduct alleged and the surrounding communications before advising on possible defences.
What Happens After This Charge
An obstruction of justice charge proceeds through the standard court process, including a first appearance and disclosure, before moving toward a resolution or a trial. Because this offence often arises alongside another criminal matter, such as an underlying charge the accused was allegedly trying to influence, the two cases may proceed together or be linked in scheduling, and a conviction can be treated seriously at sentencing given its direct impact on the integrity of the justice system. See our criminal records overview for how a conviction can affect a person going forward.
Frequently Asked Questions
Is obstruction of justice the same as obstructing a police officer?
No. Obstructing a peace officer under section 129 involves in-the-moment interference with an officer performing their duties, while obstruction of justice under section 139 targets broader interference with the justice system, such as tampering with witnesses or evidence.
Can I be charged for asking a witness to reconsider their statement?
It depends heavily on how the request is made and its intent. Genuine, non-coercive communication through proper channels, such as a lawyer, is very different from pressuring or threatening a witness to change their evidence, which can support this charge.
Does obstruction of justice require the interference to succeed?
No. The offence targets an attempt to obstruct, pervert, or defeat the course of justice, so it can apply even if the effort was ultimately unsuccessful.
What is the maximum penalty for obstruction of justice?
It is a hybrid offence with a maximum of 10 years imprisonment if the Crown proceeds by indictment, or up to 2 years less a day and/or a $5,000 fine on summary conviction. There is no mandatory minimum sentence.
Can obstruction of justice be charged alongside another offence?
Yes. It is common for this charge to be laid alongside an underlying offence when the accused is alleged to have interfered with a witness, evidence, or a proceeding connected to that offence.