There will be a contractors board in your State that you can contact for information or to file a claim against the contractor.
The subs who did work on the jobs are able to file a mechanics lien on the property so that they can hopefully get paid from that.
But, to start with, contact the State Contractors Board, or whatever it's called in your neck of the woods.
In evaluating a DUI case, the first question to ask is:
Did the police officer have a legal right to detain and question the driver, and to ask the driver to submit to a field sobriety test..(that may or may not include a portable breath test). The answers vary greatly from jurisdiction to jurisdiction, sometimes even within the same state.
Generally, to detain a driver, a police officer must have a reasonable suspicion that the driver has or is committing an infraction or some crime. Now, that being said, if the police officer watched him leave a bar, stagger to the car, fumble with his keys, etc, then the officer may have had grounds to investigate him further.
Your family friend needs to IMMEDIATELY contact the services of an attorney experienced in DUI law. The requirements for when to file various pleadings are often statutory, and your friend may have already run out of time. The attorney in your friend's state can also properly advise him on how your courts have interpreted the reasonable suspicion guidelines, and how best to proceed.
For a referrall, contact your local or state bar association.