Portland City Hall has launched an investigation of the city's ride-hailing companies, following a report in the New York Times that Uber employed high-tech software called "Greyball" to evade inspectors, beginning in Portland in 2014.

The software created ghost cars that tricked inspectors into believing that there were Uber cars nearby.

That the company was evading inspection were obvious to inspectors in 2014 when they tried to hail cabs, but the mechanism was not revealed until last week.

At a press conference Monday afternoon, Mayor Ted Wheeler and City Commissioner Dan Saltzman announced the Portland Bureau of Transportation will for 30 days examine the practices of both Uber and Lyft, by looking at, among other things, the data the company is required to provide the city as well as complaints from customers.

Wheeler says he hasn't ruled out going to the Oregon Department of Justice or other outside entities for further investigation of criminal or civil violations.

"This is a company that that has taken the time at the highest levels to create a special application for the purpose of falsifying the information on their primary app for regulators," Wheeler said.

The mayor also decried a bill the company is pushing in Salem that could undercut the city's efforts to regulate ride-hailing apps.

"While this is being revealed," Wheeler said, "the very same people are quietly working in Salem to undercut our entire regulatory framework."

Wheeler says he has no evidence either way of that Uber has discontinued the use of its Greyball software.

"I don't know whether or not local laws or state laws were potentially violated," he says. "And we don't have a confirmation yet—at least I don't have a confirmation yet—that Uber has discontinued the practice of 'Greyballing.' So all of these are on the table."

Uber didn't immediately respond to requests for comment, but has said the company has not used the software since 2014.

Wheeler says the city attorney has not yet weighed in on that plan. Saltzman says he believes the city can get the information it needs to conduct an investigation.