Nearly a full half of taxicabs tested in WUSA reporter Russ Ptacek’s latest sting operation overcharged, discharged at the wrong location, or altogether ignored customers with disabilities.

Of the 42 cabs Ptacek surveyed, 48 percent offered nothing but disservice to the customers involved in the report. And when Ptacek confronts the cabbies, they either offer lame excuses or simply speed off, sometimes with a door still ajar. A blind woman with a service dog is left to wait on the curb. When Ptacek asks the driver why he didn’t pick her up, the cabbie barks, “I thought she was waiting for someone else!” and proceeds to drive away without even closing the right rear door on busy Constitution Avenue NW.

Other cabbies were caught tacking on phony surcharges, while some dropped off their fares several blocks short of the intended destination.

It’s hardly the first instance of bad behavior Ptacek has found among D.C.’s taxi drivers. Earlier this year, WUSA found 25 percent of taxis ignored black customers trying to hail a ride.