So.....
What some cops talk about when not in public -
What would you do if you were in the back room of a computer repair shop in San Rafael, years later, with a friend and a California Highway Patrol officer named Costello was bragging to our mutual buddy that, early one Sunday morning, in the 70's, he and his CHP buddies took a pail of oil and spread it all over "13 Corners" so that those "son-of-a-bitches" on the "Sunday Morning Ride" would crash.
I didn't fall, but 5-7 people did and some were hurt and considerable vehicle damage resulted.
The officer was in uniform, short, Italian and had a mustache and he was talking to a guy named "Mike" and he didn't know me. But he sure thought it was funny. Mike didn't laugh and I was so mentally flustered that I couldn't say anything at the time.
OK - It's been years and I'm guessing that he's collecting our taxpayer paid 
for, tidy California Highway Patrol civil service pension by now:  
Costello.
.................................................
That reminds me of when I watched a CHP car cut a 90 degree corner, on Muir Woods Road crossing onto the wrong side of the road, pulling into the path of a guy - The guy could go no place except for smack into the driver's door of the CHP car, injuring him.
We found out later that the officer and another officer testified in court 
that the motorcyclist had crossed the centerline and run into the car. We found 
that out months after the court case. I still remember the officer's car cutting 
the corner and the motorcyclist locking up the rear wheel, sliding sideways and 
slamming into the driver's door and tumbling to the ground, all still on his 
own, correct side of the road.
A person's life screwed up by a cop lying.
I can only imagine the guy testifying that the cop had cut the corner and the 
two cops testifying that the rider slammed into the car and the car was on the 
correct side of the road.
The cop was even sharp enough not to slam on the brakes to leave skid marks in 
evidence on the wrong side of the road. 
It's a wonder why people learn to distrust the California Highway Patrol.
.....................................
On the other hand - I do know a lot of good officers - most of them are.