The Transportation Security Administration (TSA) reported that between March 22 and April 22 of 2020, 58 firearms were seized in passenger carry-on baggage. This compares to 346 firearms during the same period last year. When the TSA started crunching the numbers, they found that 1.24 firearms were detected per 100,000 passenger screenings this year, compared to 0.46 firearms detected per 100,000 passenger screenings in 2019. Is this a moment for celebration, or a cause for concern? The TSA has so far offered no explanation.
Comparing 2019 and 2020 air travelers is like comparing apples and oranges; they are both fruit, but the similarities end there. The COVID-19 pandemic has reduced air travel by more than 90%. Assuming the same mix of travelers in 2019 are traveling today is unrealistic. Groups that are likely not traveling today include seniors, families with small children, and vacationers. This demographic were unlikely to bring firearms to airport security checkpoints in 2019, and are not traveling at all in 2020. Removing such travelers from the 2019 firearms detection rate would result in a higher 2019 detection rate amongst likely travelers in 2020. Moreover, given the change in demographics of travelers today compared to 2019, if just one fewer firearm had been detected per day this year, then the rate of firearm detection per 100,000 passenger screenings would drop to 0.58, which is more in line with the 2019 rate. This highlights the sensitivity of the demographics on the statistics being reported.
Red teams have probed airport security checkpoints and found that TSA screeners frequently miss weapons hidden in passenger baggage. TSA screener distraction and fatigue are the likely cause of such errors. Screening as many as 150 items per hour places significant strain on screeners, resulting in items missed. It is unlikely that the 4,432 firearms detected by TSA screeners in 2019 were the only firearms carried to airport security checkpoints. It is reasonable to say that an unknown percentage of firearms passed undetected. Given that the number of screenings has dropped by more than 90% in the past month, there are fewer distractions and less fatigue, resulting in higher firearm detection capabilities and performance.
One benefit of the statistics reported by the TSA is that they can be used to assess the performance of TSA screeners. Assume for a moment that the demographics of travelers are essentially the same today as they were in 2019, and that the TSA has detected all firearms in 2020, given reduced screener distraction and fatigue. If the increased firearm detection rate is attributable solely to higher TSA screener performance, then the ratio of 0.46 to 1.24, or 37%, would represent the percentage of firearms detected in 2019, or 63% of firearms missed. This value is consistent with the miss percentage reported by red teams.
In February, a Government Accountability Office review found that TSA had not documented its process for monitoring screener training compliance. As a result, TSA agreed to begin monitoring trends in noncompliance at individual airports, an action it expected to complete by June 30, 2020. The unprecedented travel situation may have thrown a spanner in the works for meeting this deadline, given that operations are far from normal, although the lower passenger throughput will afford more time for monitoring.
Statistics offer the opportunity to uncover information and reveal insights into a system, and these firearm detection rates – and reasons for them – need closer attention. As air travel ramps up over the next year, and the broad demographic of travelers return, firearm detection rates will likely revert to what they were in 2019. Should air travelers be concerned? No more so than they were in 2019.
