In the late 1970's Jim Kowalski was a friend of mine.
I'm not embarrassed to say that, because he was an intelligent, articulate, and, by all outward appearances, very nice guy.
I knew his family, and had been to his home.
At the time, I was a teenager and worked at a comic book store on Sligo Ave. in Silver Spring. Kowalski was a customer. It wasn't unusual for us to have adult customers, and I never knew him to do anything inappropriate or suspicious regarding young customers, or otherwise.
Later, he rented space near the store and opened a pinball arcade ("Pinball Wizard"). They were popular at the time, and his seemed reasonably well-run and successful.
In retrospect, he may have opened the arcade to attract children, either simply due to his obsession with them, or to groom them. Again, I never witnessed any inappropriate behavior on his part. In fact, his own kids came there and hung out on occasions.
The first I learned of his criminal behaviors was when I saw a story on the news and heard his name mentioned. I laughed to myself, and thought, "Jim's not going to be happy to know some child molester with his name is out there."
It was quite a shock to watch the screen as my old friend, now some 15-20 years older, was led into court in an orange jump suit and shackles.
It was a disturbing personal lesson in how an outwardly normal demeanor can belie serious mental problems and criminality.