1986 was a long time ago.
If modern psychiatry can’t get him past his issues over a divorce from that far back they may as well close-up shop.
This is the result of a program the JUSTUS Dept started back around 2010. They have been mining the old databases of state and local law enforcement looking for any possible reason to deny a purchase.
As can be expected, many old hand written and typed records have errors and omissions and are not complete. This can easily occur during transfer of information from paper documents and microfiche to computer databases. Any areas with even the slightest doubt, an easily recognizable error or incongruence with verbiage or interpretation of a local, state or Federal law will trigger the reason to deny.
Even if you have passed background checks and purchased firearms lawfully for decades you will now find yourself being denied. JUSTUS will not research court records or follow-up with anyone, so the burden falls on you to clear your name. Your rights are denied without due process and you are considered a prohibited person.
The appeal process is very slow and intimidating and appears to be so by design. Since you are considered a prohibited person it also carries with it the potential, even though unlikely, that you will be subject to a friendly visit by the ATF. Should this happen, they can destroy any firearm and ammo they confiscate within 90 days. Unfortunately, even if the process goes smoothly it can easily take 12 to 15 months to clear your name. If you have to hire an attorney it can $2000 to $3000 or more, but many people would not know how to handle this on your own.