Looking at opponents cards
I play at least once a month at 5 different clubs with about 10 different partners. At one of the clubs my partner told me that the player on my left had been looking at my cards - my fault as I should have been holding them closer to my chest! I've known of two players (long gone) who were known for looking at opponents cards. I was playing a match a few years ago when one of my team mates heard, during the break, an opponent telling his team mates that I showed my cards.
Law 74C5 has something to say about this but does not make an obligation on a player to inform an opponent if they are holding their cards in a manner in which they can be seen by the opponent. Does anyone have any advice on how to deal with such situations?