War Zone in Cupertino?

On 12/29 in the evening Stevens Creek boulevard near the Vallco Fashion Park looked like a war zone. I was driving along Stevens Creek around 8PM and had to spend more than half an hour to move between Tantau and Wolfe because of the sobriety checkpoint. At least 20 police officers were standing there with sheriff cars and trucks and very bright light resembling a war zone. What's going on? They didn't even stop us for the sobriety test. So what's the fuss? It was not New Year's evce. It was not even Christmas's eve. It was a normal regular Friday night. They made Cupertino like under siege. It was only in one direction entering Cupertino. Do we want some kind of police state in Cupertino?