The Markup and Gizmodo have obtained and analyzed actual predictions for more than three dozen departments that used PredPol predictive policing software for at least six months between 2018 and 2020. This data sheet provides the findings from our disparate impact analysis and public housing analysis for Birmingham, Ala. To learn more about the project read, our investigation. For more details on how we did this analysis, read our methodology.
Predpol’s algorithm relentlessly targeted the block groups in each jurisdiction that were most heavily populated by people of color and the poor, particularly those containing public housing. The algorithm spared block groups with more White residents the same level of scrutiny.
The proportion of each jurisdiction’s Black and Latino residents was higher in the most-targeted block groups and lower in the least-targeted block groups compared to the jurisdiction overall. The opposite was true for the White population: The least-targeted block groups contained a higher proportion of White residents, and the most-targeted block groups contained a lower proportion.
For the majority of jurisdictions in our data set (27 jurisdictions), a higher proportion of their low-income households lived in the block groups that were targeted the most. In some jurisdictions, all of their subsidized and public housing was located in block groups PredPol targeted more than the median.
These vast disparities were caused by the algorithm relentlessly predicting crime in the block groups in each jurisdiction that contained a higher proportion of the low-income residents and Black and Latino residents. They were the subject of crime predictions every shift, every day, and in multiple locations in the same block group.
We also analyzed arrest statistics by race from the FBI’s Uniform Crime Reporting (UCR) Project for 29 of the agencies in our data that were in UCR. In 90 percent of them, per capita arrests were higher for Black people than White people—or any other racial group included in the dataset, mirroring the characteristics of the neighborhoods that the algorithm targeted.
We analyzed arrest data provided by 10 law enforcement agencies in our data and the rates of arrest in predicted areas remained the same whether PredPol predicted a crime that day or not.
Compared to Birmingham, Ala., overall, the most-targeted block groups had:
Compared to Birmingham, Ala. overall, the least-targeted block groups had:
| Targeting Level | Demographic | Proportion of Block Group pop. |
|---|---|---|
| Most Targeted Block Groups | Asian | 1.1 |
| Most Targeted Block Groups | Black | 50.3 |
| Most Targeted Block Groups | Latino | 1.1 |
| Most Targeted Block Groups | White | 30.9 |
| Median Targeted Block Groups | Asian | 0.0 |
| Median Targeted Block Groups | Black | 56.7 |
| Median Targeted Block Groups | Latino | 0.9 |
| Median Targeted Block Groups | White | 22.7 |
| Least Targeted Block Groups | Asian | 0.0 |
| Least Targeted Block Groups | Black | 21.7 |
| Least Targeted Block Groups | Latino | 0.2 |
| Least Targeted Block Groups | White | 64.8 |
| Jurisdiction Total | Asian | 0.4 |
| Jurisdiction Total | Black | 49.5 |
| Jurisdiction Total | Latino | 0.6 |
| Jurisdiction Total | White | 33.9 |
Compared to Birmingham, Ala. overall, the most-targeted block groups had:
Compared to the Birmingham, Ala. overall, the least-targeted block groups had:
| Targeting Level | Demographic | Proportion of Block Group pop. |
|---|---|---|
| Most Targeted Block Groups | $120k - 150k | 0.9 |
| Most Targeted Block Groups | $75k - 100k | 3.9 |
| Most Targeted Block Groups | $200k and above | 0.3 |
| Most Targeted Block Groups | Less than 45k | 54.7 |
| Median Targeted Block Groups | $120k - 150k | 0.6 |
| Median Targeted Block Groups | $75k - 100k | 3.8 |
| Median Targeted Block Groups | $200k and above | 0.3 |
| Median Targeted Block Groups | Less than 45k | 36.5 |
| Least Targeted Block Groups | $120k - 150k | 1.4 |
| Least Targeted Block Groups | $75k - 100k | 6.3 |
| Least Targeted Block Groups | $200k and above | 3.7 |
| Least Targeted Block Groups | Less than 45k | 26.5 |
| Jurisdiction Total | $120k - 150k | 1.0 |
| Jurisdiction Total | $75k - 100k | 3.7 |
| Jurisdiction Total | $200k and above | 2.3 |
| Jurisdiction Total | Less than 45k | 38.7 |
In Birmingham, Ala. 36 percent of public housing was on block groups the software targeted the most, 89 percent of public housing was on block groups the software targeted more than the median.
The table below provides how many predictions each block with public housing received. The final column tells us the percentage of days a block received predictions from PredPol’s software between Sep 01, 2019 and Jan 30, 2021. We confirmed these dates with the Birmingham, Ala., police department.
| Census GEOID | Block | Predictions | Num. Public Housing Units | Pct. days w/ Predictions |
|---|---|---|---|---|
| 010730131001 | 1001 | 1611 | 1 | 99.8069498 |
| 010730131001 | 1008 | 2234 | 9 | 99.8069498 |
| 010730039001 | 1003 | 1725 | 2 | 98.8416988 |
| 010730052003 | 3001 | 1209 | 2 | 98.0694981 |
| 010730024001 | 1015 | 1477 | 8 | 97.8764479 |
| 010730112091 | 1016 | 1117 | 2 | 96.7181467 |
| 010730055002 | 2024 | 1327 | 19 | 95.3667954 |
| 010730130021 | 1010 | 1083 | 30 | 95.1737452 |
| 010730020002 | 2026 | 1106 | 1 | 94.7876448 |
| 010730045002 | 2001 | 921 | 29 | 94.5945946 |
| 010730005002 | 2005 | 833 | 5 | 94.4015444 |
| 010730005002 | 2010 | 1088 | 8 | 92.8571429 |
| 010730040005 | 5020 | 1333 | 1 | 92.4710425 |
| 010730023031 | 1014 | 864 | 21 | 91.5057915 |
| 010730007002 | 2014 | 901 | 6 | 91.1196911 |
| 010730005001 | 1029 | 665 | 3 | 87.0656371 |
| 010730023031 | 1007 | 618 | 23 | 83.0115830 |
| 010730029001 | 1048 | 767 | 13 | 82.4324324 |
| 010730030023 | 3006 | 775 | 8 | 81.2741313 |
| 010730055002 | 2033 | 668 | 9 | 81.2741313 |
| 010730029001 | 1051 | 522 | 8 | 80.5019305 |
| 010730023031 | 1008 | 717 | 2 | 78.9575290 |
| 010730029001 | 1025 | 566 | 4 | 77.9922780 |
| 010730131001 | 1009 | 536 | 5 | 75.0965251 |
| 010730004005 | 5001 | 568 | 5 | 74.5173745 |
| 010730023031 | 1020 | 508 | 4 | 72.0077220 |
| 010730130022 | 2002 | 471 | 8 | 70.8494208 |
| 010730004004 | 4000 | 384 | 2 | 70.2702703 |
| 010730055002 | 2027 | 470 | 6 | 70.0772201 |
| 010730007001 | 1023 | 512 | 1 | 70.0772201 |
| 010730005002 | 2012 | 452 | 5 | 63.8996139 |
| 010730023034 | 4004 | 372 | 6 | 63.1274131 |
| 010730036006 | 6003 | 367 | 2 | 61.5830116 |
| 010730029001 | 1052 | 457 | 10 | 61.3899614 |
| 010730023034 | 4001 | 391 | 11 | 61.1969112 |
| 010730045002 | 2002 | 403 | 10 | 59.2664093 |
| 010730007002 | 2011 | 544 | 10 | 57.1428571 |
| 010730024001 | 1014 | 310 | 1 | 55.7915058 |
| 010730027003 | 3056 | 357 | 1 | 55.4054054 |
| 010730045002 | 2003 | 449 | 9 | 54.8262548 |
| 010730023034 | 4002 | 325 | 7 | 54.2471042 |
| 010730007002 | 2004 | 309 | 1 | 53.2818533 |
| 010730131001 | 1013 | 352 | 6 | 53.2818533 |
| 010730029001 | 1050 | 316 | 8 | 51.9305019 |
| 010730130021 | 1011 | 318 | 20 | 48.0694981 |
| 010730048002 | 2002 | 286 | 1 | 48.0694981 |
| 010730030023 | 3003 | 285 | 10 | 46.9111969 |
| 010730030023 | 3004 | 259 | 8 | 45.1737452 |
| 010730032002 | 2001 | 269 | 2 | 44.2084942 |
| 010730032002 | 2019 | 279 | 2 | 43.8223938 |
| 010730051011 | 1002 | 325 | 6 | 43.6293436 |
| 010730024002 | 2060 | 269 | 8 | 43.0501931 |
| 010730045002 | 2005 | 342 | 3 | 42.8571429 |
| 010730031005 | 5013 | 240 | 3 | 42.6640927 |
| 010730005002 | 2011 | 273 | 6 | 40.9266409 |
| 010730023031 | 1003 | 240 | 4 | 40.1544402 |
| 010730027001 | 1174 | 227 | 1 | 38.4169884 |
| 010730023031 | 1004 | 262 | 5 | 37.4517375 |
| 010730023031 | 1016 | 216 | 25 | 35.9073359 |
| 010730027001 | 1073 | 211 | 4 | 28.9575290 |
| 010730057021 | 1011 | 146 | 1 | 27.9922780 |
| 010730005002 | 2016 | 186 | 4 | 27.6061776 |
| 010730011002 | 2025 | 169 | 2 | 27.2200772 |
| 010730029001 | 1053 | 143 | 5 | 25.8687259 |
| 010730024001 | 1012 | 151 | 7 | 25.8687259 |
| 010730005001 | 1028 | 145 | 7 | 25.8687259 |
| 010730027002 | 2008 | 140 | 1 | 25.0965251 |
| 010730011003 | 3008 | 141 | 1 | 25.0965251 |
| 010730055002 | 2043 | 144 | 2 | 24.7104247 |
| 010730007002 | 2016 | 141 | 2 | 23.5521236 |
| 010730032002 | 2003 | 131 | 2 | 23.5521236 |
| 010730027001 | 1095 | 141 | 2 | 22.0077220 |
| 010730024001 | 1016 | 136 | 4 | 21.8146718 |
| 010730024001 | 1010 | 182 | 2 | 21.4285714 |
| 010730030023 | 3000 | 148 | 15 | 20.0772201 |
| 010730040004 | 4005 | 120 | 1 | 17.9536680 |
| 010730029001 | 1049 | 99 | 19 | 17.9536680 |
| 010730027002 | 2012 | 106 | 1 | 17.1814672 |
| 010730032002 | 2002 | 98 | 1 | 16.7953668 |
| 010730032002 | 2018 | 91 | 5 | 16.0231660 |
| 010730020002 | 2004 | 109 | 2 | 15.0579151 |
| 010730029003 | 3026 | 74 | 1 | 14.2857143 |
| 010730023033 | 3001 | 85 | 2 | 14.2857143 |
| 010730032002 | 2000 | 82 | 1 | 13.8996139 |
| 010730030023 | 3001 | 90 | 5 | 13.7065637 |
| 010730029002 | 2034 | 68 | 2 | 13.1274131 |
| 010730027001 | 1106 | 67 | 1 | 12.7413127 |
| 010730051011 | 1011 | 88 | 8 | 12.1621622 |
| 010730027002 | 2014 | 86 | 5 | 11.9691120 |
| 010730032002 | 2008 | 62 | 2 | 11.5830116 |
| 010730030023 | 3002 | 62 | 6 | 10.8108108 |
| 010730040004 | 4000 | 69 | 1 | 10.8108108 |
| 010730005001 | 1012 | 60 | 3 | 10.8108108 |
| 010730027002 | 2016 | 66 | 3 | 9.8455598 |
| 010730045002 | 2006 | 56 | 1 | 9.8455598 |
| 010730027001 | 1097 | 56 | 2 | 9.2664093 |
| 010730008001 | 1057 | 47 | 1 | 8.6872587 |
| 010730057023 | 3010 | 45 | 1 | 8.6872587 |
| 010730051011 | 1009 | 51 | 4 | 8.1081081 |
| 010730030023 | 3005 | 42 | 3 | 7.7220077 |
| 010730034003 | 3005 | 42 | 1 | 6.3706564 |
| 010730143021 | 1031 | 39 | 1 | 6.1776062 |
| 010730005001 | 1013 | 32 | 8 | 5.9845560 |
| 010730024003 | 3029 | 31 | 1 | 5.7915058 |
| 010730027002 | 2001 | 27 | 1 | 5.2123552 |
| 010730030023 | 3026 | 30 | 1 | 5.2123552 |
| 010730021001 | 1021 | 28 | 2 | 4.6332046 |
| 010730029001 | 1022 | 23 | 6 | 4.2471042 |
| 010730023031 | 1002 | 23 | 5 | 3.4749035 |
| 010730008001 | 1061 | 25 | 2 | 3.4749035 |
| 010730003001 | 1053 | 15 | 2 | 2.8957529 |
| 010730039001 | 1104 | 11 | 2 | 2.1235521 |
| 010730027001 | 1074 | 9 | 4 | 1.7374517 |
| 010730051011 | 1004 | 9 | 1 | 1.7374517 |
| 010730005002 | 2019 | 7 | 1 | 1.3513514 |
| 010730133003 | 3008 | 6 | 12 | 1.1583012 |
| 010730024005 | 5008 | 6 | 1 | 1.1583012 |
| 010730024004 | 4013 | 7 | 1 | 1.1583012 |
| 010730005001 | 1014 | 5 | 1 | 0.9652510 |
| 010730027002 | 2007 | 3 | 5 | 0.5791506 |
| 010730023031 | 1019 | 4 | 10 | 0.5791506 |
| 010730023032 | 2013 | 3 | 2 | 0.5791506 |
| 010730005002 | 2002 | 2 | 2 | 0.3861004 |
| 010730023031 | 1001 | 2 | 7 | 0.3861004 |
| 010730032002 | 2016 | 2 | 4 | 0.3861004 |
| 010730130022 | 2001 | 2 | 1 | 0.3861004 |
| 010730048001 | 1008 | 2 | 1 | 0.3861004 |
| 010730005002 | 2006 | 1 | 1 | 0.1930502 |
| 010730051011 | 1008 | 1 | 5 | 0.1930502 |
| 010730001005 | 5036 | 1 | 1 | 0.1930502 |
The map below aggregates all the predictions Birmingham, Ala., received in our analysis window into a 2D grid. Each square of the grid represents an area approximately 500 ft. x 500 ft., the size of the PredPol prediction box. The color represents the number of predictions that occurred within the square. The more predictions, the darker the square.