about the ongoing activities on DCE. The respondent was not entitled to
engage in any of these activities, however, if his actions would likely lead to
a breach of the peace. There are constraints on the exercise of any person’s
rights and one of those constraints is where the exercise of a right will lead
to a breach of the peace or other public safety concerns.
 In my view, this understates the importance of both the
common law liberty to proceed unimpeded along a public highway and the right to engage in political protest — the heart and
soul of freedom of expression in a democracy. At the same time,
it overstates the scope of the police power to arrest someone to
avoid a possible breach of the peace — a breach that may never
occur, and a breach that, if it were to occur, would be caused by
the unlawful actions of others. The police power to arrest for a
possible breach of the peace is an extraordinary power. Its exercise cannot easily be justified, according to the case law of this
court, which is based on the Waterfield test.
(a) The Waterfield test
 The Waterfield test sets out a two-stage analysis for
determining whether the police have acted within their authority at common law. The test requires, first, that the police be
acting in the execution of their duties. Second, in all the circumstances the police conduct must constitute a justifiable exercise
of their powers. Put another way, Waterfield requires that the
court strike a balance between the police’s public duty and of
the liberty and other interests at stake: R. v. Waterfield, 
1 Q.B. 164,  3 All E.R. 659 (C.A.); R. v. MacDonald, 
1 S.C.R. 37,  S.C.J. No. 3, 2014 SCC 3, at paras. 35-36;
R. v. Mann,  3 S.C.R. 59,  S.C.J. No. 49, 2004 SCC 52,
at paras. 24-26.
 I agree with my colleague that, in this case, the police
were acting in the execution of their duty to preserve the peace.
We differ at the second stage of the Waterfield inquiry, which is
concerned with whether the police action “constitutes a justifiable exercise of powers associated with the duty”: MacDonald,
at para. 36.
 My colleague proceeds from the premise that the public
has a right to peace and security that is in conflict with
Mr. Fleming’s freedom of expression. With respect, this mischaracterizes the nature of the conflict. The conflict in this case is not
between Charter rights; it is between the exercise of police duty
to preserve the peace and Mr. Fleming’s rights, both common
law and Charter rights, and in particular his freedom of expression. In such a conflict, Mr. Fleming’s rights enjoy presumptively