About two dozen family members and friends attended the candlelight vigil. Posters demanding justice and signed T-shirts were hung on a chain-link fence at the southeast corner of the intersection.
Family members contended that the officer was receiving special treatment.
"It's horrible that this guy isn't in jail yet," said daughter Christine. "If it was anyone else, they would be in jail now.
"I want justice for my dad. I'm not going to ever rest," she said.
Christine Farries was joined at the vigil by her sisters Tammie and Nicole Pirrone.
If the officer had died, Tammie Farries said, her father would have been arrested on the spot, and "we would be visiting him in jail."
The family has a Facebook page - "Justice for David Farries" - that had more than 1,200 likes.
In a statement Wednesday afternoon, the District Attorney's Office said that its investigators were being diligent:
"Our condolences go out to Mr. Farries' family and friends. We ask for their patience as we work as expeditiously as possible to complete the necessary and thorough investigation of this case.
"This case, as with any case where a person has lost his or her life, is examined carefully with our highest goal of developing the necessary evidence to charge. While we are mindful of working quickly, we will not do so at the expense of being accurate or thorough."
Farries, who had four daughters and seven grandchildren, was buried Monday in Magnolia Cemetery in Tacony.
Farries was driving a 1994 Ford Econoline van and the officer was driving a 2007 Dodge Charger when the accident occurred about 11:40 p.m. in Holmesburg, police said.
The officer was driving south on State and Farries was traveling east on Ashburner, police said.