Spouse with MCI insists on using computer technology without help

I took the initiative and wrote to the Department of Motor Vehicles when my mother kept telling me my father's driving was dangerous and that he shouldn't drive any more. My thinking was that if the DMV determined he was a safe driver, that would be good enough for me. I lived about 125 miles away in a different city. The DMV contacted me for more information that I didn't have. All I had was his name, address, and DOB; I did not have his driver license number. They did call him in to be re-tested. He could take the written test three times; he took it twice and failed both times. He said he couldn't remember the question when he was reading the suggested answers (multiple choice). He did not go back for a third testing. His reaction was to say that he hadn't hurt anyone by his driving up to that date and that he wasn't going to hurt anyone in the future. My mother then called me and asked me to come get their car because otherwise he would forget and would drive somewhere. Neither of my parents know I wrote to the DMV - as far as I know.