Remeasuring Border Security Effectiveness

May 13, 2013

This month, The Council on Foreign Relations, a non-partisan think tank, released a study entitled, “Managing Illegal Immigration to the United States.”

To determine overall trends in areas like apprehensions, the study relied on information from the Mexico Migration Project, a survey based on interviews with several hundred households in communities that are sources for migrants to the United States.

The CFR report confirms, with graphs like this in Figure 4, other reports that illegal migration fell through the 1990's and 2000's:

Although not a perfect science, apprehensions are a fundamental measurement to determine the overall “effective ratio” for different border sectors.

Effectiveness is at the center of the immigration debate because the Gang of Eight’s immigration proposal sets an overall goal of a 90% effective rate, which may be hard to meet.

Here's how the equation reads now: Effectiveness = (apprehensions + turn-backs) / (got-aways + apprehensions + turn-backs)

Turn-backs = People who fled back to Mexico, away from approaching U.S. agents along the border

Got-Aways = Crossers known or suspected to have evaded apprehension and entered the U.S.

But got-aways and turn-backs are based on visual observations, determined by cameras, agents in the field, and physical evidence of movement, i.e. footsteps.

It’s been recently shown that finding these visual clues isn't as simple as previously thought. High powered sensors on unmanned drones have recently found that the agency's numbers were high in got-aways, with agents catching just a fraction of the border crossers spotted.

This most recent study explores what the effective rate would look like if turn backs were subtracted from the equation. Again, here's full equation (Apprehensions + Turn backs)/ (Apprehensions + got aways +turn backs).

Full equation:

Without turn backs:

As for turn-backs, the study concludes: "Turn-backs should not be included in either the numerator or denominator of any ratio measuring law enforcement effectiveness."

Eliminating this measurement from the equation changes the overall numbers and suggests that the goals being set forth in the immigration debate might not be realistic.

The Senate Judiciary Committee struck down on an amendment last week for the entire border with Mexico to be brought under operational control before starting a path to citizenship. The current proposal only calls for the three busiest sectors to be brought up to 90 percent control.

Republican Senator Chuck Grassley warned the committee, "If we don’t make this very clear, we can have situations where 10 years down the road, we don’t have effective control."

The committee is scheduled to resume hearings on Tuesday.

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