Several episodes have similar character roles for professions and murders. Who (in your opinion) was the worst between the following similar characters:
1. Col. Rumford or Col. Braille
2. Alex Benedict or Findlay Crawford
3. Oscar Finch or Nelson Hayward
4. Dr. Fleming or Dr. Mayfield
5. Ken Franklin or Riley Greenleaf
6. Kay Freestone or Leslie Williams
7. Dale Kingston or Max Barsini
I'm sure there are many others but this should be a good start. Lets have some fun with this.
I've said it a dozen times, but Lee Grant causes me to have a real thing for Leslie Williams, so (all joking aside) that "disqualifies" me from the Leslie vs. Kay question.
Leslie Williams was worse than Kay - she was fueled by greed and completely used and killed a man that loved her.
Dr. Mayfield was worse, for trying to kill a man that was nothing but good to him, and then taking out more innocent bystanders.
I find Ken and Riley hard to differentiate because they were played by the same person, similar industries, and both characters were greedy and arrogant. If I had to choose one though, I guess it would be Ken Franklin, because he killed such a sweet guy that had, for whatever reason, let Ken take all the glory for work he had never really done - so he should have been forever grateful to him, and just retired and collected royalties.
From everything that Columbo learned about Ken's lifestyle, that insurance money would've been gone in no time anyway. So along with the nastiness of it, it was a complete WASTE.