The principle of judicial immunity protects judges from testifying to observations made during any proceedings they are administering. This principle derives from the principle of judicial independence which protects judges from certain consequences when making decisions.
This typically means that a judge cannot be compelled to testify regarding "events experienced in the course of their judicial duties" or "matters encountered in the course of exercising a judicial function". However, some suggestion is that this also means they are not competent to testify either.
Where the evidence would concern events from prior to the judge's appointment then they will be compellable.
Judicial immunity will cover chamber discussions in front of the preliminary inquiry judge.
R v Beauregard, 1986 CanLII 24 (SCC)
R v Parente, 2009 CanLII 18685 (ON SC) at para 7
Parente, ibid. at para 6, 12
Ermina v Canada (Minister of Citizenship and Immigration), 1998 CanLII 8969 (FC) at paras 5 - 11 citing MacKeigan v Hickman (1988), 43 CCC (3d) 287 (N.S.T.D.) R v Beauregard, supra at p. 69
- Parente, supra at para 10
- e.g. R v Wolf, 2007 ONCA 327 (CanLII) at para 10
- Parente, supra at para 16
Tribunals are generally not protected by the constitutional rules around judicial independence as their role is largely to effect government policy.
Judicial salaries are a means by which judicial independence is preserved.
Independence requires that independence commissions play a role in the setting of salary rates.
Ocean Port Hotel Ltd. v. British Columbia (General Manager, Liquor Control and Licensing Branch), 2001 SCC 52 (CanLII) at para 24
Ref re Remuneration of Judges of the Prov. Court of P.E.I.; Ref re Independence and Impartiality of Judges of the Prov. Court of P.E.I.,  3 SCR 3, 1997 CanLII 317 (SCC)
Provincial Court Judges' Assn. of New Brunswick v. New Brunswick (Minister of Justice),  2 SCR 286, 2005 SCC 44 (CanLII),
Provincial Court Judges’ Association of British Columbia v. British Columbia (Attorney General), 2017 BCCA 63 (CanLII)
PEI Reference, supra