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Home My WebLink AboutICPD Traffic Stop ReportICPD TRAFFIC STOP ANALYSIS ICPD STOP MAP ral Ridge Mall®, ; � Waterworks Prairie Park 1 Osh Sy O Zw:e: 1 Zoos: 2 Z.One: 3 Zone: 4 Zp z S Zptt: 6 4• Zptl: 7 Z.: S OL Cbralville sms: � Rd ¢� 6S&. os PN S n 7th �*a"� s _ 6"' y • IIIIIIIIIIIIIIIIIIIIIIIIY """ IZIW srh sr A _ Hickory Hill Park If �N \•� ZSe A �.rh. �.s Zonex 9 Zones 10 Zane:11s Zanex 12 ark Rd Zane: 14 Zonex 13 v ZoltE:'f6 " \.. v �� s ersity of Iowa. .... SrT:ef5f aoc W \al $ Universityof Iowa;' Iowa City 6 a Hospitals'and N'nics ` H SW 27 r06 — t j O E "St Z� F. rOWT Sr .� :17 zone: l8 Zooe:1 University :20 ZQy)e:$ zone: 22 �sl+p is 23 zone: 24 o Heights r^ 6 A/ - ✓WBenton St 'Kirkwood Ave A � C a m B s H 218 KN k v_� d :i --)" Zane7'27 Zonex ffi 4 t Zane: 29 Zane: 30 Zane: 3'1 *r Zone: 32 bwa City Muni o rn B � t � toarhon Trekd��g4. 27 10 Zn: 34 Zr. 3 -' - eaZn: 33 40 Ht Terry Trueblood a e Recreation Area > 6 �... .. Sycamore t - -� Li Zone: 41 Za`tl:!! vast SW Zane: 43 : M 45 s 46 .. Zone: 47 0309r2brid: 48 C , z � 5 m o n y` :E Zr ' 49 zml�- 50 Zrm 51 52 , Zee Z.- as Zr - 36 THE NUMBER OF STOPS BY ZONE 45.00% 35.00% 30.00% 25.00% 15.00% 10.00% 5.00% Percents For Department N =12850 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 57 60 64 ral Ridge Mall®, ; � Waterworks Prairie Park 1 Osh Sy O Zw:e: 1 Zoos: 2 Z.One: 3 Zone: 4 Zp z S Zptt: 6 4• Zptl: 7 Z.: S OL Cbralville sms: � Rd ¢� 6S&. os PN S n 7th �*a"� s _ 6"' y • IIIIIIIIIIIIIIIIIIIIIIIIY """ IZIW srh sr A _ Hickory Hill Park If �N \•� ZSe A �.rh. �.s Zonex 9 Zones 10 Zane:11s Zanex 12 ark Rd Zane: 14 Zonex 13 v ZoltE:'f6 " \.. v �� s ersity of Iowa. .... SrT:ef5f aoc W \al $ Universityof Iowa;' Iowa City 6 a Hospitals'and N'nics ` H SW 27 r06 — t j O E "St Z� F. rOWT Sr .� :17 zone: l8 Zooe:1 University :20 ZQy)e:$ zone: 22 �sl+p is 23 zone: 24 o Heights r^ 6 A/ - ✓WBenton St 'Kirkwood Ave A � C a m B s H 218 KN k v_� d :i --)" Zane7'27 Zonex ffi 4 t Zane: 29 Zane: 30 Zane: 3'1 *r Zone: 32 bwa City Muni o rn B � t � toarhon Trekd��g4. 27 10 Zn: 34 Zr. 3 -' - eaZn: 33 40 Ht Terry Trueblood a e Recreation Area > 6 �... .. Sycamore t - -� Li Zone: 41 Za`tl:!! vast SW Zane: 43 : M 45 s 46 .. Zone: 47 0309r2brid: 48 C , z � 5 m o n y` :E Zr ' 49 zml�- 50 Zrm 51 52 , Zee Z.- as Zr - 36 45.00% 35.00% 30.00% 25.00% 20.00% 15.00% 10.00% 5.00% Percents Days N = 3650 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 57 60 64 45.00% 35.00% 30.00% 25.00% 20.00% 15.00% 10.00% 5.00% Percents Nights N = 9200 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 57 60 64 TRAFFIC OBSERVATIONS o. 2015 traffic observations = 27,032 o. 2007-2012 traffic observations = 28,951 ► Total traffic observations = 55,983 TRAFFIC OBSERVATIONS 2007-2015 o. Zone 21 traffic observations = 11,880 ► Zone 29 traffic observations = 8,114 ► Other zones traffic observations = 7,038 ► Spread over zones 27, 28, 30 and 38 ► Observations made from 9/01/15 through 2/28/16 2015 OBSERVATIONS WE FOCUSED ON ZONES WHERE MOST STOPS WERE MADE Previous traffic stop observations and 2010 Census Bureau data suggest that about 10% of the drivers on the roads in most areas of Iowa City are minority°°°�� drivers—both days and nights. ► Percentage white ► Percentage African-American ► Percentage Hispanic/other ► Percentage Asian ► Percentage minority (total) 89.0070 04.0070 03.0070 04.0070 07.0070 ZONE 21 DAYS (DOWNTOWN AREA) ► Percentage white ► Percentage African-American ► Percentage Hispanic/other ► Percentage Asian ► Percentage minority (total) 74.00% 16.00% 02.00% 08.00% 18.00% ZONE 21 NIGHTS (DOWNTOWN AREA) ► Percentage white ► Percentage African-American ► Percentage Hispanic/other ► Percentage Asian ► Percentage minority (total) 73.00% 23.00% 02.00% 02.00% 25.00% ZONE 29 DAYS (BROADWAY AREA) ► Percentage white ► Percentage African-American ► Percentage Hispanic/other ► Percentage Asian ► Percentage minority (total) 68.00% 31.00% 01.00% < 01.00% 32.00% ZONE 29 NIGHTS (BROADWAY AREA) ► Percentage white ► Percentage African-American ► Percentage Hispanic/other ► Percentage Asian ► Percentage minority (total) ZONE 30 DAYS & NIGHTS 78.00% 15.00% 02.00% < 05.00% 17.00% ► Percentage white ► Percentage African-American ► Percentage Hispanic/other ► Percentage Asian ► Percentage minority (total) ZONE 28 DAYS & NIGHTS 86.00% 13.00% < 01.00% < 01.00% 14.00% Please keep in mind that roadside observations are simply a sample of the drivers on the roads. As such, the values indicated in the results should be treated as estimates with a fai interval generous confidence DAYS 45.00% 35.00% 30.00% 25.00% 20.00% 15.00% 10.00% 5.00% Percents Days N = 3650 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 57 60 64 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 nr or min ppea-- 13 20 29 21 22 27 28 percent minority stopped days benchmark ► The highest degrees of disproportionality is concentrated in areas where the fewest stops were made ► A disparity index shows that the average degree of disproportionality across all areas of town was approximately five percentage points higher than the corresponding benchmark values. ► The index gives a ballpark estimate of disproportionality. AVERAGE DISPARITY ACROSS ZONES Zone 27 Days Zone 27 Days race Freq. Percent Cum. Asian/Pacific Islander 16 7.02 7.02 Black/African American 39 17.11 24.12 Caucasian 164 71.93 96.05 Latino/Hispanic 3 1.32 97.37 Other 5 2.19 99.56 Unk 1 0.44 100.00 Total 228 100.00 Zone 28 Days Zone 28 days race Freq. Percent Cum. Asian/Pacific Islander 12 4.29 4.29 Black/African American 60 21.43 25.71 Caucasian 189 67.50 93.21 Latino/Hispanic 10 3.57 96.79 Other 5 1.79 98.57 Unk 4 1.43 100.00 Total 280 100.00 Zone 30 Days Zone 30 Days race Freq. Percent Cum. Asian/Pacific Islander 7 2.69 2.69 Black/African American 66 25.38 28.08 Caucasian 164 63.08 91.15 Latino/Hispanic 17 6.54 97.69 Native American/Indian 2 0.77 98.46 Other 3 1.15 99.62 Unk 1 0.38 100.00 Total 260 100.00 NIGHTS 45.00% 35.00% 30.00% 25.00% 20.00% 15.00% 10.00% 5.00% Percents Nights N = 9200 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 57 60 64 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Percent of Minority Drivers Stopped -- Nights 13 20 21 22 27 percent minority stoppednights benchmark K.] KIS: ► The highest degrees of disproportionality is concentrated in areas where the fewest stops were made ► A disparity index shows that the average degree of disproportionality across all areas of town was approximately five percentage points higher than the corresponding benchmark values. ► The index gives a ballpark estimate of disproportionality. AVERAGE DISPARITY ACROSS ZONES Zone 20 Nights Zone 20 Nights race Freq. Percent Cum. Asian/Pacific Islander 56 11.43 11.43 Black/African American 90 18.37 29.80 Caucasian 302 61.63 91.43 Latino/Hispanic 28 5.71 97.14 Other 8 1.63 98.78 Unk 6 1.22 100.00 Total 490 100.00 Zone 27 Nights Zone 27 Nights race Freq. Percent Cum. Asian/Pacific Islander 14 6.73 6.73 Black/African American 46 22.12 28.85 Caucasian 129 62.02 90.87 Latino/Hispanic 3 1.44 92.31 Native American/Indian 1 0.48 92.79 Other 10 4.81 97.60 Unk 5 2.40 100.00 Total 208 100.00 Zone 28 Nights Zone 28 Nights race Freq. Percent Cum. Asian/Pacific Islander 61 10.30 10.30 Black/African American 105 17.74 28.04 Caucasian 360 60.81 88.85 Latino/Hispanic 36 6.08 94.93 Other 19 3.21 98.14 Unk 11 1.86 100.00 Total 592 100.00 Zone 30 Nights Zone 30 Nights race Freq. Percent Cum. Asian/Pacific Islander 20 5.08 5.08 Black/African American 92 23.35 28.43 Caucasian 250 63.45 91.88 Latino/Hispanic 26 6.60 98.48 Native American/Indian 1 0.25 98.73 Other 2 0.51 99.24 Unk 3 0.76 100.00 Total 394 100.00 OFFICER LEVEL ANALYSIS (% Minority / Min. Benchmark) : (% W&A / W&A Benchmark) Kol Disparity Index 1 Em OUTCOMES Minority-yes/Minority-no) : (White-yes/White-no) ► Values > 1 suggest disproportionality ODDS -RATIOS OR = 0.73 no yes Total minority 545 29340 29885 white 19437 89400 99837 Total 19982 109740 129722 WARNINGS OR = 1.28 no yes Total minority 29371 514 29885 white 89420 19417 99837 Total 109791 19931 129722 CITATIONS OR = 1.97 no yes Total minority 29612 273 29885 white 99342 495 99837 Total ARRESTS 119954 768 129722 OR = 1.99 no yes Total minority 29688 197 29885 white 99488 349 99837 Total 129176 546 129722 SEARCH REQUESTS citations 2010 2011 2012 2013 2014 2015 arrests 2005 2006 2007 2010 2011 2012 2013 2014 2015 2005 2006 2007 search requests 2010 2011 2012 2013 2014 2015 hit rates a 2015 Results suggest a degree of racial disproportionality in traffic stops conducted by the ICPD. A ballpark estimate of the level of disproportionality indicates that minority drivers were stopped on average about five percentage points higher than the observation benchmark values. Comparatively little traffic stop disproportionality was found in areas of town where the lion's share of traffic stops were made. Most disproportionality occurred in areas where stops were less frequent. Individual officer analyses show that two officers' disparity index values were considerably higher than other officers' values. SUMMARY ➢ Disproportionality in most stop outcomes decreased in recent years. The single exception was citations, where disproportionality increased. It should be noted however, that odds -ratio values for citations were comparatively modest. ➢ In recent years, officers were about twice as likely to arrest a minority driver as others during a stop ➢ In recent years, officers were about twice as likely to request a voluntary search from a minority driver as from other drivers. This occurred even though seizures or hit rates resulting from voluntary searches were about the same for minority and non -minority drivers. ► Overall, results suggest that the levels of disproportionality in stops and outcomes is trending lower. SUMMARY