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Is Discipline Due Diligence?

In an Occupational Health and Act (“OHSA”) prosecution, the best defense is “due diligence”. In that regard, courts have held that discipline can be an element of due diligence. However, whether the discipline was reasonable enough to avoid the offense turns on whether it was “proportionate” and “effective” under the circumstances. This blog post discusses those two concerns:

(A) Discipline that was Proportionate

There are no occupational health and safety prosecutions where the court considered whether discipline was proportionate to the offense with respect to a due diligence defence.[1] However, in labour arbitrations, arbitrators have determined that disciplinary responses to misconduct must be proportionate to the seriousness of the risk of injury.[2] For example, in Dominion Malting Ltd., the arbitrator found that: “[t]he safety of the workplace at all times must be of paramount importance…. The Employer, and each and every employee, without exception, must meticulously comply with every safety directive. That is an obligation imposed … by the employer and certainly by the legislation…”[3] There, the employee’s dismissal was upheld because he did not follow the lockout procedures established for operating a dangerous machine in addition to having been previously disciplined for the same misconduct.[4] Likewise, in Sheet Metal Workers’ International Assn., Local 473 v. E.S. Fox Ltd., the grievance concerned the suspension of an employee for failing to wear fall protection.[5] In the result, the grievance was dismissed because the arbitrator found that the employee was working at height where the risk of injury from a fall was significant and the potential harm to the employee was large, which warranted serious discipline.[6] The arbitrator went on to state that “deterrence is an important consideration in health and safety in that employees should know that any significant breach of safety procedures will result in severe discipline”.[7]

Arbitrators have also made an exception to the labour law rule that discipline should be progressive and corrective in nature where misconduct had potential consequences of significant injury. In other words, arbitrators have upheld dismissals for first time violations of matters where health and safety was jeopardized in a serious manner. For example, in Re Corporation of the City of Brampton and the Amalgamated Transit Union, Local 5173, the arbitrator stated that “…where the potential consequences of the breach are severe … the employer has the right to by-pass the normal progressive disciplinary response.”[8] Similarly, in Re Wardair Canada Inc. and Canadian Airline Flight Attendants’ Association, the arbitrator considered that the grievers had no previous disciplinary records and that the safety infraction was serious. The arbitrator dismissed the grievance, holding that:

when the potential consequences of the breach are severe and could impact upon the lives of passengers and other crew members as well as the property of the company, an employer has the right to bypass the normal progressive disciplinary response which it might have invoked for a breach of a safety rule of lesser consequence.[9]

Labour arbitrations have also discussed whether discipline was appropriate considering the obligations imposed on employers by the OHSA. For example, in Ontario Hydro, the Ontario Labour Relations Board held that employers must be armed with the right to discipline employees for health and safety violations for two reasons.[10] First, if collective bargaining prevented effective discipline, the employer would fail to meet “its due diligence” obligations under the OHSA.[11] And second, the employer would fail to maintain a safe workplace.[12] In that case, the griever was discharged for possession of marijuana at a nuclear facility.[13] In dismissing the grievance, the Board stated that “the employer is under a statutory obligation to maintain a safe workplace and to take reasonable steps to ensure that employees are not exposed to preventable risks… One element in a prevention program is the imposition of discipline, to deter employees who might be disposed to break the rules.”[14]

In sum, arbitrators have held that discipline should be proportionate to the risk of health and safety caused by the misconduct. In addition, arbitrators have held that discipline is required to prevent workplace health and safety contraventions by deterrence. As such, by analogy to OHSA prosecutions, discipline should be proportionately serious to the risk of health and safety caused by the contravention.

(B) Discipline that was Effective

In addition to demonstrating that discipline was proportionate to the seriousness of the offence to prove due diligence, case law suggests that employers should show that discipline was “effective” in preventing OHSA contraventions. “Effective” discipline is discipline that was “reasonably” deterrent in the circumstances. For example, in Regina v. Wilson’s Truck Lines Limited,[15] the court held that an employer did not take every precaution “reasonable” with regards to occupational health and safety, and therefore, failed to prove a due diligence defence because it did not properly discipline its employees.[16] There, the court found that there were no written warnings, dismissals or suspensions for breach of safety procedures.[17] By analogy, effective discipline can therefore be described as discipline that begins with documented warnings that escalates to suspensions and dismissals for breach of safety procedures.

In contrast, “ineffective” discipline has been described by the courts as discipline which permits a “culture of discretion” with respect to health and safety. For example, in R. v. Moran Mining and Tunnelling Ltd.,[18] the employer appealed a conviction for failing to ensure the use of a fall-arrest system, arguing it had satisfied the defence of due diligence.[19] However, the appeal was dismissed.[20] The employer did not discipline its employees with regard to fall-arrest protection, and therefore, it was not unreasonable that the employer did not prove due diligence.[21] Although the employer maintained a satisfactory fall-arrest system, employees made their own decisions about whether to use the fall-arrest system.[22] As well, employees were never meaningfully disciplined for not being tied-off.[23] The only evidence of any discipline of an employee was the single occasion when an employee’s supervisor verbally cautioned him for not wearing fall-protection.[24] Accordingly, such an ineffective form of discipline promoted what the court called a “culture of discretion”, which, in turn, caused the employer’s failure to prove due diligence.[25] By the same token, in Ontario (Ministry of Labour) v. Reid & Deleye Contractors Ltd.,[26] the employer appealed a conviction for failing to ensure the use of a fall-arrest system, arguing that it had proved due diligence.[27] In the result, the appeal was dismissed because the employer’s Health and Safety Coordinator knew that employees at the project were not working in compliance and that there was a “culture of discretion” where discipline was not handed out for violations.[28] Alternatively, where discipline was handed out at the project, it was ineffective.[29] For example, warnings were made verbally to employees. However they were not documented, which, in the words of the trial judge, was “a lax procedure”.


To rely on the defence of due diligence, the defendant must prove that it properly disciplined its employees where it was reasonable to do. If so, the discipline must have been “proportionate” and “effective” under the circumstances.

[1] Rather, OHSA cases seem to suggest that discipline must be “effective”.

[2] See Rheem Canada Ltd. v. United Steel, Paper and Forestry, Rubber Manufacturing, Energy, Allied Industrial and Sevice Workers International Union [2012] O.L.A.A. No. 346; Consider also Employment Law in Canada, which follows a similar line of reasoning. In determining whether employee misconduct should lead to dismissal, the Supreme Court of Canada, in McKinley v. BC Tel, has set out an analytical framework involving a contextual approach. Inherent in the contextual approach is the principle of proportionality, including a consideration of the seriousness of the misconduct.

[3] [1995] M.G.A.D. No. 73.

[4] Ibid.

[5] 2003 CanLII 20165 (ON LRB).

[6] Ibid.

[7] Ibid.

[8] 19 L.A.C., (2nd) 37.

[9] 19 L.A.C., (3rd) 99.

[10] [1997] O.L.R.D. No. 2888.

[11] See Canadian General Tower Ltd. and United Steelworkers of America, Local Union 862 (Schramm) [2003] OLAA 801 at para 160.

[12] See ibid.

[13] Ontario Hydro, supra, note 10.

[14] Ibid.

[15] [1998] O.J. No. 3219.

[16] Ibid.

[17] Ibid.

[18] 2006 CanLII 19042 (ON SC).

[19] Ibid.

[20] Ibid.

[21] Ibid.

[22] Ibid.

[23] Ibid.

[24] Ibid.

[25] Ibid.

[26] 2011 ONCJ 472 (CanLII)

[27] Ibid.

[28] Ibid.

[29] Ibid.