Community leaders say the ruling sends the message that officers are rarely held accountable.
They also urged citizens around the city to keep calm and let the justice process take its course, as an appeal could deliver a different outcome.
"As a community, it is crucial though that we remember that while seeking justice, it should not involve violence or the destruction of our community and our neighborhoods. We must find peaceful ways to express our frustrations and concerns," said Catherine Hicks.
Charges against Dial were dismissed earlier this week.
A judge ruled that prosecutors had not presented evidence showing he committed a crime.
Judge dismisses all charges against Philadelphia police officer Mark Dial after fatal shooting
City officials say a peaceful protest followed that decision.
A district attorney quickly filed a motion to appeal.