Editor’s note: As part of our 10th anniversary, Behind the Badge is sharing stories from our archives on Tuesdays and Fridays. This story is from August 27, 2015. Happy (sober) St. Pat’s. It’s an uncommon scene, and most of the time people think something is wrong. When four Tustin police officers walked into the bar on a Friday night, the initial reaction was a raised eyebrow. But it didn’t take long before people lined up to learn why the police were there — education, not enforcement. Tustin police held their fourth Know Your Limit campaign Aug. 21 at four local…