RIPA Update for Los Altos

 The helpful folks at the city recently provided me with the RIPA data through August, so it's a good time to check in on the State of Los Altos Policing for the first half of the year.

It's been a fairly quiet summer on the police policy front, with a few high-visibility arrests using ALPRs, and discussion going on about purchasing drones for the police. Here's what we are seeing on the data front -- after all, this is a data blog!

RIPA Stops

As you all know by now, every police department in California is required to collect data on every single stop that they make. This data, suitably anonymized, is then public. You can get this by submitting a public records request to the City; I've also put it in the github repo, along with all the analysis code, if you'd like to look at it yourself.

Here are the stops per month since Los Altos started collecting RIPA data.

As you can see, the vast majority of stops are for traffic violations. There are lots of ways you might want to measure what the police do, but clearly traffic enforcement is a large part of it.*

Also interesting is the spike that happened in the Fall of last year. After a dip around the holidays, it went back up, and for most of this year it has been substantially higher than it was in 2022 and the first half of '23. Note that other kinds of stops did not increase.

Traffic stops are usually a function of how many cops are out making stops, rather than a change in citizen behavior. Probably they decided to put more cops out on traffic patrol. 

Racial Differences

Let's compare stop rates by race -- are people of color stopped more often than average?** The following chart shows how likely a person of each race is likely to be stopped, relative to a White person.

As we've seen before, people of color are stopped more frequently than White people in Los Altos. In fact, with the recent increase in traffic stops it appears that that bias is increasing.

There is a reasonable objection to this. There are very few Black and Hispanic people who live in Los Altos.*** Those folks are coming from out of town, so using the Black or Hispanic population of Los Altos unrealistically inflates these numbers.

We can test this, by thinking about how many Black and Hispanic people would have to come into Los Altos every day to even out these numbers?  That is, how many visitors would have to be in town so that the per-capita stop rates would be the same for all races?  We can do that math.

Race	How many would need to visit Los Altos every day
Black	1,918
Hispanic	11,624
Asian	4,979

It's pretty clear that there is no way that many people of color are traipsing through Los Altos each day. Where would they park?

Crime Rates

Last year we looked at crime rates from CityProtect and found that they were actually pretty low on the Peninsula in general, and in Los Altos in particular. What has happened since then?

After a strange drop in the second half of 2023, property crimes are back up -- but still just over half of what they were during the pandemic. Rates are slightly lower than they were in 2017.

Basically, the takeaway here is that property crimes have been up and down, but are about they same as they were seven years ago. And crime here is lower than the average property crime rate in cities under 100,000 people. Things are pretty good!****

How about violent crime?

Violent crime is also up after that strange dip, but again we see ups and downs but no real lasting change over the last seven years. We are quite a bit safer than the national average though!

Conclusion

Crime continues to be at roughly the same low rates we have always enjoyed. There is no "crime wave" in Los Altos. Traffic stops are up (I hope to learn more about that from the Chief soon), and bias remains stronger than any of us would like.

The root causes of that bias are very complex. Some of it is due to bias by proxy; fixing that means changing the attitudes of the people. Some of it is also likely due to bias in policing methods. We should be taking all the steps possible, on all fronts, to combat this bias, and make Los Altos as safe for people of color as it is for White people.

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* This raises some interesting questions that I don't know the answers to. How much of our police budget goes to traffic enforcement? Generally, municipalities keep the revenue from traffic fines. How much does Los Altos get from those traffic fines? Is it more or less than it costs to do the enforcement? Questions for another day...

** To find out, we have to look at the number of stops by race, then divide by the population by race. That gives us the "stops per capita by race." We can then divide that by the "stops of White people by race" to get the relative stops per capita by race.

*** Hmmm, why might that be? The Color of Law has the answer. 

**** Data from the Real Time Crime Index, taken 29 Sep 2024.