Much of the country, and the world, have been shocked by the cruelty of the Trump administration’s zero-tolerance, arrest-everyone-and-separate-parents-and-children policy. In the face of criticism, administration officials have contended that the policy promised to “deter” potential future migrants from attempting the journey.

That assertion would meet its big test in the number of migrants whom Border Patrol apprehended in the month of June. With the “zero tolerance” policy going firmly into effect around May 5, and media reports of family separations accumulating by the end of the month, would fewer people try to cross the U.S.-Mexico border in June?

Actually, the number of migrant apprehensions nearly always goes down from May to June, for seasonal reasons: it is scorchingly, dangerously hot in the arid deserts along the southwest border. So in order to judge “deterrence” resulting from zero tolerance, we need to know whether the reduction was more than the seasonal average.

Yesterday, July 1, Associated Press reporter Elliot Spagat got a leak of a preliminary June apprehension figure. The drop from May to June 2018 was 15.6 percent, from 40,344 apprehensions to 34,057.

Border Patrol furnishes monthly apprehensions data since 2000, allowing us to judge whether 15.6 percent is abnormally high. It isn’t.

Between 2000 and 2017, the average monthly drop from Mays to Junes at the U.S.-Mexico border was 21.3 percent: 5.7 percentage points steeper than 2018’s drop of 15.6 percent. The May to June 2018 drop in migration was smaller than the average of the previous 18 years, showing no deterrent effect at all.

Between 2011 and 2017, a period of sharply reduced migration, the average May-June drop was much lower: 11.3 percent. The May to June 2018 drop in migration, then, was 4.3 percentage points larger than the average of the previous 7 years, showing only a very modest potential deterrent effect.

Had 2018 matched the 2011-2017 average, Border Patrol would have apprehended 35,785 migrants at the border. Instead, it apprehended 34,057. The difference is 1,758. So perhaps that is about how many migrants were “deterred.” Not much.

For all of the pain and outrage it has caused, during a month when it was at its most intense and generating worldwide headlines, the “zero tolerance” policy had only an extremely modest deterrent effect on would-be migrants.

Instead of this cruel wrong turn, it’s beyond time to focus on the violence, corruption, and misrule pushing tens of thousands of Central Americans out of their home countries.

Year May-June Change May June
2000 -30.8% 166,296 115,093
2001 -27.5% 122,927 89,131
2002 -19.3% 97,424 78,655
2003 -14.8% 88,690 75,530
2004 -20.3% 118,726 94,590
2005 -21.6% 115,823 90,786
2006 -35.2% 105,450 68,366
2007 -19.4% 88,504 71,338
2008 -22.2% 69,233 53,854
2009 -9.5% 50,884 46,044
2010 -30.0% 47,045 32,955
2011 -13.0% 31,236 27,166
2012 -17.0% 36,966 30,669
2013 -21.5% 43,856 34,436
2014 -4.6% 60,683 57,862
2015 -7.2% 31,576 29,303
2016 -14.6% 40,337 34,450
2017 10.8% 14,519 16,087
2018 (unofficial) -15.6% 40,344 34,057
Average May→June decrease 2000-2017 -21.3%
Average May→June decrease 2011-2017 -11.3%
Source: http://bit.ly/2F1UHsc