Doesn't matter if he got her information off the ticket he wrote - that information is CONFIDENTIAL. It was given to him under duress, as part of providing ID for a traffic violation. It was not given to him "personally" - that is a very different thing. It's not a secret, in fact it's virtually "shouted into his face" during training, over and over again. Not just once, not twice; over and over, repeatedly. Private, Confidential, protected, personal - I don't know of any other words to make it more clear.
The mere act of a policeman using this information against another man, woman or child is rehensible. My wife works for the airlines, and has access to practically any politician or celebrity's personal information you can think of. Name the artist, actor, businessman or politian; and chances it's in her company's database. If she's bored at work, and even looks at this our of morbid curiosity - she will be fired. It's literally that bluntly stated. The words "Private and Confidential" have both meaning, and consequences.
I agree, it just seems stupid that he would leave a paper trail. He could have just waited outside the building and ‘bumped into her’.
Come on,this guy used the data base, leaving a key stroke trail. He then left a note on her car. He is a cop he could have followed hr around and ran into her at the grocery store.