And it made him think.

His timing could hardly seem better, with technology rapidly democratizing the instruments of forensic research and the purview of young architects widening. He begins his recent book, “Forensic Architecture,” recalling the libel trial in London of the Holocaust denier and historian David Irving, nearly two decades ago. Mr. Irving’s shameful case relied on a tidbit of architectural evidence: he made much of fuzzy satellite imagery showing a demolished crematory at Auschwitz. Survivors had said they recalled poison cyanide gas canisters dropped through a hole in the crematory’s roof, but Mr. Irving said there was no hole in the satellite photos. “No hole, no Holocaust,” became the deniers’ catchphrase.

Mr. Irving lost his trial. But Mr. Weizman cites the case as a cautionary tale. The tools of forensic analysis can easily be perverted. Wielded especially by governments and other powers in defense of violence and crime, they need to be challenged by equally sophisticated means. Architecture and forensics may be disparate disciplines but brought together they could produce a new, “different mode of practice,” Mr. Weizman realized. They could help reverse “the forensic gaze” back onto state agencies “that usually monopolize it.”

Adopting a phrase coined by the photographer Allan Sekula, Mr. Weizman terms the practice “counter forensics.”