The vehicle was on private property when this took place? Was he followed while he was on the streets. DWI/OWI is not a valid charge when on private property unless the copwitnessed him driving upon public roadways and met himat private property for the stop. But if he never left the property, nothing can be done with the suspected OWI and/or the concealed weapon charges. This can be interpolated from Hamden.
That should nullify the charge right there, Look at the case-law in Hamden for the answer.
Can you list the statute numbers that he was charged with? can you add more detail?
Try and get some more details on this situation,