Photo by Pak Gwei.

An anonymous rider program that checks D.C. cabs for violations found that 27 percent refused to pick up passengers for an illegal reason in a one-month period.

Among 308 rides hailed 30 days after August 28, 84 drivers were cited for refusal to haul. Among 300 rides hailed during the same period, 28 cabs had non-functioning credit card readers, a slip from a 96 percent reliability rate to 91 percent.

According to the D.C. Taxicab Commission, anonymous riders include “African Americans and whites, males and females, and a range of ages, as well as an individual in a wheelchair and a person requiring the assistance of a seeing-eye dog.” While it would be useful to know which of these passengers driver refused to pick up — race-based complaints are most common — a spokesperson said “specific demographic data … must be withheld to maintain the integrity of this on-going operation.”

Cab drivers can only refuse service to people who are “severely inebriated” or if they “fear physical harm.”