A Labor Day weekend test of cab drivers by anonymous riders found familiar problems.

According to the D.C. Taxicab Commission, 20 of the 63 drivers tested between Thursday and Monday were cited for a violation, including ten for failure to haul and five for non-functioning credit card readers. While a release states that the anonymous riders were black and white, male and female, and ranged in age, it doesn’t state who among the group wasn’t picked up by a cab driver. However, the release says that drivers did not refuse to drive a person in a wheelchair and another person with a seeing-eye dog.

Request for comment from DCTC with a breakdown of who cab drivers refused to pickup was not immediately returned. Location of the violations was also not included in a release. Update: A DCTC spokesperson says “specific demographic data regarding anonymous riders must be withheld to maintain the integrity of this on-going operation.”

While complaints filed with DCTC did not show this, a WUSA-9 report and anecdotes revealed that black residents are regularly not picked up by drivers. With the Office of Human Rights, the DCTC launched a new filing method earlier this year to report alleged discrimination and violations. The commission is also considering a van service in areas primarily east of the Anacostia River where people are historically underserved by cab drivers.