Engineering Professional Practice

Sub-contractor Mr. A was severely beaten by his labors because he had not paid them for more than seven months. During investigation it was revealed that client did not pay to the contractor and contractor did not pay to the subcontractor. The client didn't pay because consultant did not submit the necessary bill report. The consultant says the work is defective and quality of the work is not as per specifications. While the contractor does not agree because it was not informed on site and blames that the consultant wants covert money. Discuss the case considering contract law, tort, liability and negligence whatsoever applicable.