Malicious prosecution

Upchurch v. Oshawa (City), 2014 ONCA 425:

 [16] The elements of the tort of malicious prosecution require a plaintiff to prove:

1. The prosecution was initiated by the defendant
2. The prosecution was terminated in favour of the plaintiff
3. The prosecution was undertaken without reasonable and probable cause. In the context of a public prosecution by the Crown or an individual Crown attorney, this means that there were not objectively speaking reasonable grounds to initiate or continue the prosecution or that subjectively, the prosecutor did not subjectively believe that proof to the required standard could be made in a court of law
 4. That the prosecutor acted with malice, that is to say, used the office of prosecution for an improper purpose. (See Miazga v. Kvello Estate, 2009 SCC 51)

[17] Absent these requirements, neither “errors in judgment or discretion or even professional negligence” are sufficient to establish the intentional tort of malicious prosecution. (See Nelles v. Ontario, [1979] 2 S.C.R. 170)