Waterston relates to role Ex-‘Law & Order’ actor stars in HBO’s ‘The Newsroom’ ‘Newsroom’s’ Sam Waterston finds it easy to relate to his character

Sam Waterston (center) is shown on the set of “The Newsroom” with Thomas Sadoski (left) and Jeff Daniels.

LOS ANGELES — When Sam Waterston sits down in a corner booth at a posh Beverly Hills hotel, one expects rarefied reflection from this stage and screen actor best-known for his 16-season portrayal of crusading prosecutor Jack McCoy on “Law & Order” — and, sure, he gets to that.

But more surprising is the way he dissolves into boyish laughter as he describes watching Jeff Daniels, his co-star in HBO’s “The Newsroom,” in a bathroom scene in “Dumb and Dumber.”

“I didn’t watch the movie until we already shot quite a bit” of “The Newsroom,” the 71-year-old actor says in his distinguished, gravelly voice. “You can understand how it wouldn’t be my thing. But the scene in the bathroom is absolutely genius. The expressions that take over his face — it was surprisingly impressive and outstanding.”

The way the Massachusetts native brightens when talking about his co-star’s impeccable work in that scene is similar to the pride his character takes in the news in Aaron Sorkin’s lofty ode to journalism, set inside a cable news show. Waterston plays Charlie Skinner, a kooky, bow-tie-wearing, unapologetically old-school president of the news division — or as Daniels described him by phone, “the wizard behind the curtain ... who’s had a couple of Scotches.”

Waterston finds parallels with the well-seasoned newsman he portrays: “The appetite Charlie has for news — no matter how much he’s seen and no matter how cynical that’s made him — the appetite for the news never goes away. “He’s going to be that way until he’s gone. That’s kind of easy for me to relate to because that’s how I feel about acting.”

The workplace drama, which premiered last month to a solid 2.1 million viewers and has been renewed for a second season, attempts to make a statement about the state of cable news shows through the prism of Daniels’ Will McAvoy, a popular anchorman whose high-minded ambitions have been sullied by the chase for big ratings — that is, until his idealistic executive producer (and ex-girlfriend) MacKenzie McHale, played by Emily Mortimer, comes back into his life and urges him to reclaim the fourth estate.

“We need more idealistic people to give their lives to journalism,” Waterston said. “It could stand a little raising of the tone.”