Uber and Lyft, and others, want hailing a ride to be as common as catching the bus. But their aggressive expansion plans are being stymied in many places in the U.S. by lawmakers because of safety concerns, pressure from taxi companies or a desire to level the playing field for incumbents, writes CNBC.

Some methods lawmakers are using to thwart their expansion include introducing requirements on driver fingerprinting, vehicle inspection, insurance, fees, and limits on where drivers can pick up and drop off passengers.

Much to the chagrin of taxi and limousine companies, ride-hailing services — whose popularity has irrecoverably slashed the value of a once-prized taxi medallion in places like New York City — have proven addictive to America’s urban population, particularly at the often heavily subsidized prices they offer riders.

Today, 34 U.S. states and more than 69 cities have passed legislation governing ride-hailing companies, also known as transportation network companies (TNCs). Another six states have enacted legislation mandating minimum insurance requirements.

Even still, some lawmakers and taxi and limo companies are pushing for more stringent regulation on things like driver fingerprinting, pick-up locations and fees. Future regulatory battles around worker classification and autonomous vehicles promise to keep things interesting.

The two private companies are spending millions to lobby politicians, reach voters with ads and lure riders with promotions. At the same time, competition in the already aggressive ride-hailing business keeps getting tougher.

This Autumn Alphabet’s Google is jumping into the market with a service built on its popular Waze app.

To streamline the hurdles ahead, both Uber and Lyft would like to see more states enact TNC-friendly legislation governing key markets. Fingerprint-based driver background checks — which some lawmakers believe are vital safety measures and taxi and limousine owners want to level the playing field — remain a big sticking point.

Uber and Lyft have argued that fingerprint-based background checks do nothing to improve safety and act as a disincentive for drivers to sign up, reducing the quality of their services. Both prefer their own self-administered background checks, which they say draw on more up-to-date information and are less onerous for drivers.

CNBC lists some places in the U.S. where friction between the companies and government is particularly acute: Texas, New York, Massachusetts, Florida and New Jersey.

• Increasing friction between US municipalities and Uber, Lyft.