What if any changes to police deployment patterns might reduce violent crime? Hotspot policing vs. ↑ resources for detectives

A friend emailed to ask my opinion of “hotspot” policing tactics being promoted by Houston PD. Here’s how I responded:

There are SO many studies on this topic, many of them very micro-focused and not particularly useful, let me give you a big-picture, 50-year overview of the research findings on this.
One of the most robust findings in criminology is that patrol doesn’t reduce crime overall or make people feel safer (going back to a major field study in Kansas City in the ’70s), and police staffing levels appear to have no relationship either way to crime going up or down.
However, this result didn’t sit well with police or their advocates, and in the 1980s, criminologists began to revisit the question, this time shrinking both the geographic areas examined and the time periods considered. Finding a negative result wasn’t considered a failure of the tactic, just evidence that the geographic and temporal constraints hadn’t been sufficiently narrowed. Eventually, they were able to demonstrate that flooding a neighborhood with police to perform stop and frisks and/or pretext stops correlated to reduced reports of serious crime IN THAT GEOGRAPHIC AREA for whatever period of time they kept it up. There are a bunch of studies out there like that.
However, few of the hotspot studies I’ve ever seen claim this is anything more than a short-term effect that goes away as soon as police leave.  And most researchers will admit it’s likely crime just bleeds into other geographic areas, the way air moves to the sides when you squeeze a balloon.
N.b., generally, what you see when these studies are portrayed in the policy arena is a bait and switch. Cops say “hot spot policing works” then use that to call for increased staffing. But we KNOW increased staffing doesn’t correlate to greater safety. The hotspot research is about deployment of EXISTING officers, not an argument for hiring more overall.
Finally, if I were making public-safety recommendations for Houston based on the current data, I wouldn’t be focused on patrol or hotspot policing, but beefing up the detective ranks, maybe even AT THE EXPENSE of patrol. Again: The real issues are how officers are deployed, not how many there are. 
There are 200 Narcotics Division detectives at HPD – far more than in homicide. I’ve argued Narcotics should be entirely disbanded, and those detectives should be moved to investigate 1) homicides and 2) shootings that do NOT result in death. The latter are almost completely ignored but are essentially similar to the murder cases; whether the victim lives or dies has more to do with the EMTs and doctors than the intentions of the shooter. (I’m not generally a fan of the Manhattan Institute, but they recently published a report reaching the same conclusion.) 
So that’s the redeployment I think we should be pushing for if the goals are to reduce racial disparities (they’re TERRIBLE in Narcotics) while reducing violent crime: Expansion of detective resources to investigate non-fatal shootings. That’d do FAR more to improve safety than anyone would ever claim for hotspot policing.

If you ask what police are actually DOING to reduce crime in hotspot areas, criminologists have no answer. It boils down to what I’ve dubbed the “Scarecrow Theory” of policing: Their mere, occasional presence wards off potential criminals. But cops aren’t deployed theoretically, and as a practical matter, what they do while they’re there (if they’re deployed to a hotspot and not responding to IRL crime reports) are traffic stops and stop-and-frisks of pedestrians. And most of the people with whom they engage are not and never will be shooters; there’s a disconnect between the strategy and the desired results.

I don’t consider it some radical position to say homicides and non-fatal shootings should be better investigated: Clearance rates for murder in Houston have declined from 89% in 2011 to 49% last year. And “hotspot” policing would do nothing to change that dynamic.

If the problem you want to solve is violent crime, focus on violent crime. Don’t engage in generalized harassment in black and brown neighborhoods then assume reduced murders will somehow be a secondary effect.