DISTRICT ATTORNEY Seth Williams announced yesterday he is convening a grand jury to investigate last week's fatal Center City building collapse to determine if anyone else - besides excavator operator Sean Benschop - should be criminally charged.

And City Council President Darrell Clarke said yesterday Council also will investigate the collapse. A Special Investigative Committee will be tasked with examining the city's procedures and regulations pertaining to licenses, permits, construction, demolition, on-site safety and worker certification.

Williams' office charged Benschop, 42, on Saturday with six counts of involuntary manslaughter, 13 counts of recklessly endangering another person and one count each of causing a catastrophe and risking a catastrophe. Benschop turned himself in and is being held without bail pending a June 26 preliminary hearing.

Benschop reportedly had marijuana and painkillers in his system when he was operating the excavator. Jennifer Selber, the assistant district attorney in charge of homicide investigations, said there was also evidence he wasn't using the machinery properly.

"So those two things taken together mean that he is responsible," Selber said. "It doesn't mean that other people aren't responsible as well. We just don't have the evidence yet."

The grand jury, which will allow Williams' office to issue subpoenas, demand documents and interview witnesses, will also examine the city's role and its policies in the calamity.

Meanwhile, Council's investigatory committee, which includes members Jannie Blackwell, Bobby Henon, Curtis Jones Jr., Jim Kenney and Maria Quinones-Sanchez, will hold hearings over the summer, make recommendations and subsequently introduce legislation to improve the city's construction standards.

"At the end of the day, this Council will come up with a set of recommendations and this Council will enact legislation that we hope will create some of the strongest standards in the nation," Clarke said.

Mayor Nutter, who learned of Council's plans via a news release, seemed to welcome an investigation into the collapse. Last week, he said the inspector general will also investigate.

"The point for us is to take the information and do something with it and make things better," Nutter said.

The mayor has proposed beefing up inspectors in the Department of Licenses and Inspections by six for a total of 46, but Clarke said Council will consider extra funding for even more inspectors.

On Twitter: @Jan_Ransom

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