By Tony Hanson

PHILADELPHIA (CBS) – A Philadelphia Grand Jury continues to investigate the deadly collapse of the Center City Salvation Army store in June.

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Criminal charges have already been filed. and the defendants are awaiting their initial court hearing in the New Year.

Heavy equipment operator Kary Roberts, also known as Sean Benschop, was charged with manslaughter and other offenses shortly after the collapse. He was allegedly high on marijuana.

A conspiracy charge, and another defendant, demolition contractor Griffin Campbell, were added by a grand jury in November.

DA Seth Williams says Campbell was at the center of culpability — that he ignored safety for profit:

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“The two of them had a unity of purpose in what they were doing as they were demolishing the building in what we know, and they should have known we believe the evidence will show, should have known was an unsafe practice. They should have been taking the building down brick by brick, floor by floor, as opposed to the method they were employing really was just for again greed.”

Attorney’s for Campbell and Roberts have denied their clients are responsible.

The investigation will continue in 2014.

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