In my new novel, your character drinks a Coke, has some Doritos and then uses his Xerox machine to copy some documents. Sounds fine, right? Authors mention trademarked goods all the time. But according the the Authors Guild, that may be a thing of the past if a new bill is passed by Congress. The bill would drop express protection for "noncommercial use" of a trademark and would weaken the protections for those who use trademarks in news commentary. The bill has already passed the House and went to the Senate Judiciary Committee yesterday.
What? You have got to be kidding me. These companies typically pay big bucks just to get movies, TV, books, comic books, even online comic strips for "product placement". It's so wide spread that there are groups who are lobbying to get tougher restrictions on in-content based advertising.
I don't see how on earth this can be enforced, especially when you include daily news broadcasts, newspapers, web sites and blogs. Fiction would be the easiest to police, obviously. The real issue is when the trademarks are used in a way that either hurts or dilutes the trademark. Some marks that have suffered from this are thinks like Coke which people use to mean all soda's or Kleenex when people are talking about tissues and Walkman when people mean "portable tape recorder". These are all marks that have lost almost all of their original branding because they've been used so much in generic terms. I don't have a clue how to solve that little problem but I don't think banning writers from including them would hurt anything.
The resolution of the crime is neatly tied up, even a bit surprising when the killer's identity is revealed.