The police don't have the power to check with your doctor without your permission. I have nothing to hide so i have no problem giving permission. They don't get your medical records the doctor is asked if any treatment would affect your ability to own a firearm.
Quote Police Service N Ireland Firearms application.
A18 I give my consent for the police to approach my GP, consultant or other medical authority to obtain factual details of my medical history if necessary.
OK, so what happens if you see a psychiatrist for your phobia of aluminum cans as well as your regular General Practitioner.
The psychiatrist tells the cops, sure I don't see a problem while your GP is completely against guns and based on this alone tells the police he doesn't think it's a good idea for you to have a gun. Which doctor trumps which? What rules do they follow for making such a decision concerning your rights? What is the criteria?