Sean Benschop, 42, was found to have marijuana and prescription painkillers in his system 2 hours after the disaster and will face six counts of involuntary manslaughter as well as counts of risking a catastrophe and reckless endangerment for his role in the collapse, sources told NBC-TV, Philadelphia.
City police detectives raided Benschop's home Friday afternoon and took away desktop computers, a hard drive, a notebook and boxes filled with documents, the TV station said.
Neighbors said Benschop regularly drove the backhoe from his Olney home to construction sites around town. He is a convicted felon and describes himself as self-employed, sources told the TV station.
Some Philadelphians had said they had complained about shoddy work at the demolition site.
The side of the building being demolished at 22nd and Market streets fell away Wednesday and tumbled onto a Salvation Army thrift store next door.
Fourteen people were pulled alive from the building.
Inspectors had found no violations at the site, The Philadelphia Inquirer reported Friday.
Some people reported making complaints before the disaster.
Patrick Gillespie, head of the Philadelphia Building and Construction Trades Council, said brick workers, working at a site next door to the collapsed building, had reported problems to the Department of Licenses and Inspections and the Occupational Safety and Health Administration, but were ignored.
Stephen Field said he made a citizen's complaint to the Department of Licenses and Inspections about "pieces of facade hanging over a subway exit" at the demolition site May 14.
"I didn't fathom the idea of it falling on a Salvation Army [building]. But there were people walking on that sidewalk. The fact that they could not see anything wrong with that is extraordinary," he said.
License and Inspections Commissioner Carlton Williams said Thursday the department typically doesn't inspect demolition work in progress, but instead relies on OSHA to look into safety issues.
"If that's the city's normal procedure, to just let it fly, I find that breathtaking," said Jay McCalla, a deputy managing director under former Mayor John F. Street.
Mayor Michael Nutter launched an inspection campaign because of the collapse.
The city issued work-stop orders at two buildings being demolished by Griffin Campbell Construction Co., the company working on the Market Street building, the newspaper reported.