Joel Warner reports that "live-audience sitcoms are turning to laughter ringers, folks so good at guffawing they're planted the audience and get everyone else cackling at the right moment." He profiles Lisette St. Claire, the woman who pioneered the business:
To prove her folks are right for the job, St. Claire picks up her phone and dials one of her go-to laughers, one of the Group A hotshots. "Give me a laugh," she says, and puts him on speakerphone. Never mind it's 7:30 in the morning, that the man on the other end has just been woken up. A dramatic, spontaneous cackling erupts from the phone, causing the early-bird crew working around us in the casting office to look up and smile, and a few chuckle themselves.
The Dish 