Taxi advocates in yellow T-shirts took the first row in a crowded session Thursday on Miami-Dade legislation designed to legalize Uber and other app-based ride services that already compete with cabs in South Florida. Photographed are, from left to right, Coral Cab manager William Pratt, drivers Humberto Becerra and Rafael Gerard, and owner Jerry Moskowitz. DOUGLAS HANKS MIAMI HERALD

To operate legally in Miami-Dade County, Uber may first have to win its latest battle over fingerprinting drivers.

On the heels of a deadly Michigan shooting spree by an Uber driver, county commissioners on Thursday argued for requiring extensive criminal checks that would include fingerprint screening for the app-based ride service and its competitors. Uber has successfully fought fingerprint checks in most jurisdictions, but now faces resistance from Miami-Dade leaders in what would be one of its largest markets.

“Based on what’s happening across the country, I don’t think we can put too many things in place that would protect our community,” Commissioner Barbara Jordan said during a day-long “workshop” on proposed county legislation that would legalize the app-based services without requiring fingerprint checks.

Uber and its smaller competitor, Lyft, are lobbying for passage of the bills, which allow the companies and taxi owners to screen their own drivers for criminal histories and driving violations. Though some large cities require app-based drivers to submit to fingerprint screening for criminal history, Uber has passed the word to commissioners that the rule would prompt the company to pull out of the Miami market.

“They have already agreed to these terms in other communities,” Jordan said. “And to hear the language that if we put these kind of things in place, ‘we’re going to walk?’ Then I say: Get to trottin’.”

Jason Dalton, the Uber driver charged with six counts of murder in Kalamazoo for last weekend’s shootings, had no known criminal record or history of mental illness. In a statement, an Uber spokesman suggested fingerprinting could be a drawback for drivers from some minority communities and that searching local, state and national criminal databases provides adequate screening.

“No background check is perfect,” spokesman Bill Gibbons wrote. But the system used by Uber and others “stacks up well against the alternatives, without unnecessarily discriminating against minority communities as fingerprint-based checks do.”

Since launching its Miami-Dade operation in June 2014, Uber reports more than 10,000 drivers compared to just over 4,000 licensed taxi operators. While county regulators cite Uber drivers for violating for-hire rules, the thriving Miami-Dade business is pressuring elected leaders to pass legislation or face the same kind of backlash that forced Broward last year to undo regulations that Uber opposed.

Broward initially required fingerprinting drivers, but backed off once both Uber and Lyft made good on threats to leave the market last summer. By the fall, Broward had adopted legislation pushed by the companies.

Both companies need a constant churn of part-time drivers to provide both the blanket coverage and competitive rates that have made the services so popular. Company executives and lobbyists argue the fingerprint requirement would turn off too many would-be drivers and damage their business models.

During their discussion, Miami-Dade commissioners noted both Houston and New York City require Uber drivers to submit drivers’ fingerprints for background checks. The county currently does not require taxi drivers to undergo fingerprint checks. Only owners of the actual taxi medallions — required for each cab in use — must submit to the test. They then are free to hire licensed taxi drivers who haven’t been fingerprinted.

The plan under discussion Thursday would be to require fingerprint screening of all for-hire drivers in Miami-Dade, whether working for Uber or operating a traditional taxi. Commissioner Rebeca Sosa invoked the Kalamazoo shooting in arguing for more screening of all professional drivers.

“For me, safety is the most important thing. I want to make sure that driver is someone who is fit for that position,” Sosa said. “Not someone that can go crazy like the one did the other day and kill people.”

Commissioner Esteban “Steve” Bovo, the legislation’s sponsor, said he was “open” to a discussion on fingerprint screening but said no law could catch “a person who passes all background checks available, and just snaps.”