"We will never be able to say for sure whether those protests led to any spread of the virus from one person to another because we don't collect that information when people come in for testing," said Farley.
Protesters were urged by city officials to get tested but they weren't required to disclose that they were protesting.
Farley announced on Tuesday that Philadelphia won't be reopening under a modified green phase as planned this week, citing an increase in coronavirus cases. Farley also stated that he doesn't believe the protests played any major role in the increase.
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"I can say that if (the protests) were to cause a substantial increase in the spread, I would have expected an increase earlier. We are seeing an increase now, and it appears this increase now is younger people who were involved with social events. I don't believe the protest had a big impact, but I'm not sure and we'll ever know."
According to Farley, over the past couple of weeks, positive cases have been likely to be younger people. Thirty-four percent of the cases were under age 30 in the past two weeks, as opposed to 20 percent during the entire pandemic.
The city will reevaluate the reopening plan on August 1.