Over a cacophony of honking taxicabs, an organizer using a megaphone led a group of drivers in a call-and-response on Washington's Freedom Plaza on Tuesday morning:

"What do we need?"
"Justice!"
"When do we need it?"
"Now!"

The cabbies were out protesting ridesharing apps like Uber and Lyft for the third time in recent months, this time to draw attention to the D.C.  Council's final vote on a bill that will allow such services to operate permanently within the law in the District.

The legislation would require app-based services to provide primary insurance cover of at least $1 million from when a driver accepts a call to when they drop off the passenger, as well complete criminal background checks on all drivers -- benchmarks most major services already meet. It also prohibits private vehicle-for-hire services from accepting street hails like taxicabs can and requires the services to submit to the city 1 percent of their gross receipts for trips beginning in the District.

Those new rules would still leave the services facing fewer regulatory hurdles than do DC taxicabs, who must pay hundreds of dollars of fees to operate in the city and who navigate a more complex set of licensing requirements. Those differences, the cabbies argue, give the services an unfair leg up over traditional taxis, which they say are losing business to their high-tech competitors.

"If I have to be licensed, all other drivers should have to follow the same rules," Earth Clark, a longtime D.C. taxicab driver who is the recording secretary of the Teamster-organized Taxi Operators Association Leadership Council, said at the protest.

Clark says she has been driving a cab in the city for 45 years but that the emergence of services like Uber and Lyft have made it hard for her to earn a living.

Not all protesters were taxicab drivers. Leslie West, a recent law school graduate, joined the group. She believes the current regulatory situation gives the ridesharing apps an "unfair advantage" over cabbies.

During the protest throngs of cabs circled the plaza, slowing the surrounding blocks to a crawl and honking horns so loudly that some bystanders covered their ears with their hands as police worked to keep the flow of traffic moving.

The inconvenience seems unlikely to have endeared the taxi driving community to their riders -- but D.C. cabbies are far from alone in staging mass protests against ridesharing services.

In June, taxi drivers across Europe staged demonstrations to highlight their concerns about services like Uber and Lyft cutting into their business. The movement has been met with mixed results. Last month a German court upheld a ban on Uber in Berlin, but a different court in Frankfurt overturned a nationwide ban on the service.

In August, Virginia agreed to allow Uber and Lyft to operate in the state under a temporary agreement while a Maryland commission ruled that Uber should comply with the same regulations as common carriers.