If you know you're being scammed by a taxi driver, you can tell him to take you to the nearest police station to let them sort out the dispute. If he won't take you (and he probably won't), tell him that you have his taxi number and will go to the police and file a complaint. Besides becoming the focus of an investigation, this will also cost him time sitting in the police station and having his taxi meter inspected. Don't assume that the police won't be interested. One tourist reported that the police in Istanbul were rather grateful for the report, since the Istanbul municipal government was as fed up with taxi scams as the tourists were. Besides the police, you can also report taxi drivers at the places listed below.
Istanbul Taxi Complaints
Toplu Ulaşım Hizmetleri Müdürlüğü
Beylerbeyi Caddesi No: 4
+90 (212) 453 7878
Turkey Taxi Complaints
Association of Taxi Drivers: Each province in Turkey should have a local chapter of the association of taxi drivers. Get the contact information from one of the taxi stands.
Transportation Department: Found in each Turkish province, this organization mostly deals with taxi stands.
For taxi meter scams, file a "complaint check" request to the local Ministry of Science, Industry and Technology in your province. You will need to fill out a form, and the ministry will check the meter. If it is found to be faulty, they will start legal actions against the driver. Unfortunately, the check has to be paid for by the complainant, so ask if the ministry will do this as part of their regular inspection services.
Turkey Taxi Scams: A guide to the various scams employed by Turkish taxi drivers.