Footage from body cameras taken as police responded to a call about Walter Wallace Jr shows him emerging from a house with a knife as relatives shout at officers about his mental health condition.
The video also shows Wallace was incapacitated after the first of 14 shots officers fired at him, lawyer Shaka Johnson said on Thursday, describing video he says police showed him and members of Wallace's family before its public release along with 911 calls.
"I understand he had a knife but that does not give you carte blanche to execute a man, quite frankly," Johnson told reporters outside Philadelphia City Hall.
"What other than death did you intend when you shoot a man - each officer - seven times apiece?"
The family does not want the two officers, who have not yet been publicly identified, to be charged with murder, Johnson said, because they were improperly trained and didn't have the right equipment.
The video shows "instant panic" from officers whose training taught them only how to open fire, he said, noting he saw no viable attempt to deescalate the situation.
"What you will not see is a man with a knife lunging at anyone that would qualify as a reason to assassinate him," Johnson said.
Police also faced rebuke from Philadelphia leaders as the anguished city bemoaned the department's response to a year of extraordinary and sometimes violent unrest.
The City Council, joining leaders of other cities, voted to block police from using tear gas, rubber bullets or pepper spray on peaceful protesters after hearing hours of testimony from people injured or traumatised by them, including a group hit with tear gas.
"It was undisciplined, it was indiscriminate and it hurt a lot of people," said Council Member Helen Gym, who introduced the bill.
The moves follow days of protests, store break-ins and ATM thefts after the death of Wallace, a black man, that led the mayor to lock down the city Wednesday night.
The family called on Monday for both medical services and police but only the latter arrived, Johnson said.
Less than 30 seconds into the encounter, Wallace was dead, felled by a blast of 14 bullets.
Police have said the two officers fired after Wallace ignored orders to drop a knife. Wallace's mother and wife were outside, shouting to police about his mental health problems, Johnson said.
In a news conference Wednesday, chief Danielle Outlaw lamented the lack of a behavioral health unit in a department she joined only this year.
She pledged to address that need and also told council she supports the goal of their bill, which she said aligns with current police policy.
Mayor Jim Kenney also supports the ban in principle but wants to review it before signing it into law, a spokesman said.
The city had a strong record of accommodating protesters in recent years, until Black Lives Matter protests erupted in the city on May 30, following the death of George Floyd.
Chaos and violent clashes ensued and broke out anew this week after Wallace's death in a mostly black section of west Philadelphia.