The contractor on trial in a deadly building collapse that killed six people on Market Street said Wednesday that he was given a contract to demolish several buildings despite having very little experience in the field and having never formally bid on a job before.

Griffin Campbell took the stand in his own defense at a trial in which he is accused by prosecutors of doing work so shoddy that it amounted to murder. 

The victims died after a three-story wall that was looming over a one-story Salvation Army thrift store toppled over, and that Campbell received multiple warnings about it. Thirteen people were also injured in the accident. 

RELATED: Aftermath: Market Street building collapse after one year. 

But Campbell’s lawyer Bill Hobson has argued that Campbell was a small fry who was too inexperienced and too unsophisticated to have criminal responsibility. 

Campbell, 51, said he was handed the job by an architect and key prosecution witness Plato Marinakos, who he considered a friend, who helped him fill out city paperwork, get a general contractor’s license with the city and even negotiated adequate insurance for the job on the contractor’s behalf. 

During about two hours on the stand Wednesday, Hobson pursued a line of questioning designed to underscore his argument that Marinakos supervised Campbell on the job.

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Wearing a white collared shirt and speaking in an even-toned voice, Campbell testified that he got his start as a businessman operating a food truck in North Philly. He used money from that to rehab houses around his neighborhood. Along the way, he took odd jobs shoveling snow, mowing lawns and working for concrete companies.

“I never in my life turned a job down,” Campbell said. “I want to work.” 

He met Marinakos as development near Temple University was heating up, and he introduced the architect to rehabbers in North Philly looking to convert row homes into housing for students, Campbell said. 

Another friend got him a job tearing down a building near 15th and Erie in 2012. It was his first demo job. Months later, Marinakos approached him about doing tearing down four buildings on Market Street. 

Campbell expressed concerns that he had never taken on a project this large before, and he had never bid on a project — most of his jobs coming from friends. 

Marinakos, Campbell testified, measured the building for him to help develop the $85,000 contract. 

“He was going to be there,” Campbell said. “His office was around the corner. If I called him he was there,” Campbell said.

A co-defendant, Sean Benschop has pleaded guilty in the case. 

Campbell will face cross examination on Thursday.