Modern taxicabs in the country had their origin in 1970 when the government took measures to give Mexico City an affordable taxi transport.
The colors changed again in 2008 this time to maroon with golden rooftops and a row of the city symbol, the Angel of Independence.
Originally they were yellow with white roof, until they were changed in mid-90s (allegedly because of yellow color being the official color of the Partido de la Revolución Democrática who at the time was competing for the newly created position of Head of Government of the Federal District with the Partido Revolucionario Institucional which is mostly identified with the green.
However, due to the increasing demand for public taxicabs, and the difficulties and cost of obtaining such license, there are many illegal 'pirata' taxis.
Pirata taxis pose a higher security risk for passengers due to the lack of background checks for drivers, and can be distinguished because they carry a regular private vehicle licence plate (which is brown in the format XXX-YYY where X a number and Y a letter) or have a number drawn or printed in place of a licence plate instead of a taxicab licence plate (which is in the format LXXXXXX where X is a number).