This book, rich in both detail and analysis, is the definitive source on political policing in Canada. It should be of interest to all those interested in Canadian history as well as to specialists in the history of policing and intelligence.

Although the few who maintain the illusion of objective history may criticize, the authors candidly declare that their history of political policing is “a secret history of conservatism, the targets of state surveillance form a kind of roster of Canadian radicalism over the decades” (11). The authors support this thesis with plenty of evidence, including the surveillance of two left-of-center political parties in Canada.

The book starts with crisp case studies that reveal important continuities in political policing. Canada responded to the threat of Fenian invasions with the suspension of habeas corpus and the use of military commissions in the 1860s and 1870s. The invasions failed, but a Fenian sympathizer assassinated an Irish-Canadian politician who opposed the Fenians. Political violence was present in Canada from the start.

The second chapter demonstrates how the securitization of immigration and transnational security threats are not new phenomena. Canada denied entry to those suspected of supporting Indian independence, and shared such intelligence with India and England. In 1914, Canada's head spy was murdered by a former informer.

The bulk of the book is composed of six chapters on “the remarkable persistence of the Red Menace” (535). The authors argue that the the Royal Canadian Mounted Police (RCMP) was biased against communists as opposed to threats from the right. The evidence that they rely on includes that: 1) the RCMP successfully campaigned against the legalization of the Communist Party even after the Soviet Union joined the Allied forces during World War II; 2) it allowed Nazi war criminals into Canada after the war, while barring those with communist sympathies; 3) it passed on damaging information to the United States that led to future Prime Minister Trudeau being barred from entry to the United States; 4) it shared information with the United States that, when subsequently leaked, led Canadian diplomat Norman Robertston to commit suicide in 1957, and 5) it spied on Canada's social democratic political party.

The authors demonstrate the contemporary relevance of their history by noting how decisions to have RCMP agents and informers testify in court both in 1920 and 1931 traded criminal convictions of Communists for valuable sources of intelligence. This theme is expertly picked up in the final two chapters on post-9/11 developments, where the authors observe the struggles of Canada's lead intelligence agency in dealing with increased demands for the use of their intelligence as evidence in terrorism prosecutions. The authors also demonstrate how the state opportunistically used both criminal and immigration proceedings against perceived radicals in the 1930s and suspected terrorists in the 2000s. The post-9/11 chapters also examine how scandal and successful litigation has frequently resulted when Canadian security officials have co-operated with American security efforts. An interesting subtext of the book is the differences between American and less populist Canadian approaches to security both during the Cold War and the post- 9/11 era.

Three chapters describe the genesis of the Canadian Security Intelligence Service (CSIS) in illegalities committed by the RCMP in the wake of the October Crisis of 1970. The book reveals a tangled and confusing web of governmental directives on Quebec separatism that allowed the Trudeau government to engage in “plausible deniability” for RCMP illegalities in the wake of the October Crisis; denials that now have “become less plausible” (323).

The book examines how conflict between the RCMP and CSIS contributed to Canada's worst intelligence failure, the 1985 Air India bombings that resulted in 331 deaths. Wiretaps were destroyed and not promptly translated to produce actionable intelligence, and the poor handling of human sources botched a subsequent trial. Fortunately, the agencies have co-operated better in post-9/11 terrorism prosecutions.

The book ends with an analytical conclusion that highlights the major themes that run throughout the chapters, including Canada's responsiveness to—at first British and then American—security concerns, the constant tensions between the demand of law enforcement for evidence and the demand of intelligence for secrecy, and the blurring of the line between a legitimate focus on espionage and political violence and more problematic concerns about subversion.

Any book of this scope and ambition can be criticized for inevitable omissions. In my view, a chapter on the political policing of Aboriginal people in Canada would have been a valuable addition. Nevertheless, the book promises to be the definitive source on political policing in Canada for decades to come. It is well written, and produces important new information and insights that should attract a wide audience.