You got to give Inspector Trout a LITTLE credit...

The film's highly jumbled view of Trout or Scotland Yard doesn't help him.

He isn't seen bringing a coroner, staff biologist, forensic photographer (they finally remember to put one in at Dr. Longstreet's residence) or a code inspector who would know the venting or pest history of the building and surrounding areas (he's told right there about a recent lethal bee attack) directly to the first crime scene before the body is removed--just a bunch of his gumshoes--so he loses authority right there. He gets reamed almost instantly in his next scene by his first level of supervisor (Crow) merely asking for immediate support on a murder case, which generally means he will be either constantly overruled or even technically replaced. He then castigates his assistant Tom for not having more evidence assembled within a single day of the first death so he decides to go completely solo to interview three consecutive vital case witnesses that the department has no previous experience with: 1) Vesalius [who not only doesn't assist Trout by mentioning other potential new victims located within medical licensing boards or bonded insurance companies, but is also allowed to sift through irreplaceable state-owned printed medical information on his own. Trout is also eventually so comfortable with Vesalius' knowledge of police procedures that he simply assigns him to interview other witnesses]; 2) the jeweller who made Phibes' amulets; and 3) the rabbi, meaning the eventual court hearings will have to rely on Trout's prodigious memory. As the corpses keep piling up by midpoint including one in the victim's own car, Trout--knowing full well by now that Phibes and a potential female accomplice flagrantly drive around town and travel internationally handsomely while stopping at banks using multiple accounts--steams in his office without even ordering his traffic division to begin stopping or tailing anybody with unusual license plates, wiring Swiss authorities for Phibes' last known visa application, or alerting border agents. Trout's final major administrative insult is about 50 minutes into the film when Trout's own division head, Waverly--a second level of ascending supervisor walking in on him--is not only played by an actor three years younger than him but also completely brushes him off (and addresses Crow by name three separate times while Trout just stands there). We won't even mention Trout being present during the two final murders since he's at least managed (or stumbled) to get 70 men behind him by then.

To his credit, Trout does redeem himself at the climax at Phibes' mansion leading the rescue, and if I recall correctly he is treated more moderately in the sequel. But by then they've shipped him off to the Middle East anyway.