A reader wrote to ask:
Is it appropriate, when writing dialogue, or even when writing informative bits, to reference name brands of today?
Example: My story is set in today; the dialogue in question is between a boy and his father discussing whether or not they will be going to a baseball game. I originally included specific teams of today (the Los Angeles Dodgers vs. the San Francisco Giants), but now I'm questioning if that is too real. Is it? should I make up a new team, with a fictitious name?
Stick with the real teams and other brand names...as long as they're just background. You might want to create fictitious names if your story purports to tell (say) the inside story on corruption in pro baseball.
By the same token, you can mention real people as long as you don't invade their privacy or defame them. So father and son could go to the game and watch Barry Bonds hit a home run—and I hope that describing such an event helps to advance the story or throw light on your characters. Not sure you'd want to have them go on to discuss his drug issues.
So you can make fair use of companies, government agencies, and real people. Back in the 1930s, Upton Sinclair wrote a series of thrillers in which President Roosevelt was a running character, giving orders to secret agent Lanny Budd.
The problem lies in defaming or invading the privacy of such persons. Then you could be in trouble.
Apart from legal trouble, the chief reason for creating a fictitious agency or community is to meet the needs of your story. Maybe you want a town something like Evanston, Illinois, but with a tough neighbourhood that doesn't really exist. So you create "Hunterston," and design the town to your specifications.
I've chosen my examples consciously: Evan Hunter (a pen name) used another pen name, Ed McBain, to write his 87th Precinct novels. They're set in "Isola," a city a lot like New York, but with its own geography and neighbourhoods. That made it possible to develop plots that wouldn't work in a "real" New York.