If I'm remembering correctly, it was a small point of issue among many other bigger issues that Al Pacino's Serpico drank tea in the movie. This was America in the early 70s and it seems like at the time, tea was relegated to women, foreign people and hippies. Or at least that's probably how the NYPD saw it. Male cops drank coffee then, when they were on stakeouts or when they were at their desks smoking and pushing papers around in ugly precinct offices. And it was surely overbrewed and bitter coffee for the most part, but that's what you as a cop drank and you just didn't have any weird fruity tea bag string floating out of your cup.
So beyond Serpico's shaggy hair and beard, unusual policing methods and annoying integrity, he insisted on drinking tea instead of coffee. That freak. Nowadays he'd have all kinds of health studies and more expansive mindsets to allow his tea drinking, and a far greater selection of readily available brands -- like Stash's Double Bergamot Earl Grey, which as a bergamot lover I was happy to find. Stash notes how its bergamot comes from the "small Citrus Bergamia tree...grown in the southern part of Calabria, Italy." And how they don't use other citrus oils in their Earl Grey, just pure bergamot, now double-strength and hopefully on the shelves of a supermarket or Target near you. More bergamot for the everyday people -- that's always good news.