TV seasons are like dog years — one TV year equals seven in human time.

That's why even the sharpest shows run out of steam after Year Five or so. 

So what does it mean that Law & Order — which premiered in 1990 (that's right: 1990) — should be on life support. 

Guess again. 

Law & Order just wrapped its 12th and it was its most popular season ever. 

An average of 19 million viewers watched it every week, its highest ratings in its history. 

More important, it is still talked about, still respected (no Saturday Night Live spoofs yet) and still fresh. 

"I think there were a variety of forces at work this year," to explain the show's success, says series creator Dick Wolf, who continues to executive-produce Law & Order and its spinoffs, SVU and Criminal Intent

"We've been very fortunate the past three years to have The West Wing as our lead-in, which was the first time in literally 10 years that we had a lead-in," Wolf says. "We've definitely benefited from the popularity of West Wing." 

Just look at the raw numbers. The season before "West Wing" arrived on the scene, Law & Order averaged 14 million viewers — solid numbers, especially for a show with historically weak lead-ins (anyone remember Now, Pursuit of Happiness, Men Behaving Badly or Working?). 

But in 1999 — when West Wing debuted at 9 p.m. Tuesdays to critical and public acclaim — Law & Order attracted nearly three million more viewers at 10 p.m., and its numbers have continued to rise ever since. 

"There is a comfort zone with shows like Friends and Law & Order," says Wolf. "These are touchstones of the American psyche in terms of how long they've been around. 

"They're like comfort food in their continuity, to be overly grandiose about it." 

Wolf's new series, Crime & Punishment, debuts June 16 on NBC.

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