Ah, I don't quite remember the episodes names... Basically there were Lassiter, Shawn and Gus talking in the police station, when, at a certain point, Lassiter ducks under the table when a girl walks past them. They get up and he explains that he snogged her at the company picnic, then they go back to talk. He then ducks under the table again, only this time it's a MAN that walks past them.

"Musta been a hell of a picnic..."

And then there's that time when he got drunk and ended up spooning the coroner...