You know how the news media are always being accused of convicting people (think JonBenet Ramsey's mother)? Well, NBC News has decided to embrace that concept, at least for one night.

Tuesday's edition of its newsmagazine "Dateline," which airs at 10 p.m., will encourage viewers to go online to convict or acquit in a real but little-known case as it's being profiled on the show.

The hour-long segment, a collaboration with Court TV, will update a case involving an apparently picture-perfect couple, Linda Stangel and David Wahl, who met at work in the fall of 1994. That relationship ended abruptly when Wahl took a walk down the Oregon coastline; he was later found dead on a beach in Washington state. Did he jump or did she push him? Viewers will be encouraged to register "guilty" or "not guilty" by logging onto the "Dateline" Web site. The results will appear at the bottom of the television screen and will be updated every 15 seconds. At the end of the broadcast, a final tally of the viewers' votes will be displayed. Then, it'll be done all over again for the West Coast feed.

And, if the experiment proves popular, "Dateline" executives may make the interactive feature a regular part of segments based on Court TV collaborations.

WB has changed the content rating for its "Buffy the Vampire Slayer" season finale from TV-PG to the tougher TV-14. The finale is set to air Tuesday, July 13; it originally was scheduled for May 25 but was yanked because it included a scene in which the graduating students of Sunnydale High School take up arms against the town mayor, who has, as WB explains it, "transformed from public official to pure demon." I'm not even gonna touch that one.

WB execs decided it was better not to air the episode while real school graduation ceremonies were taking place around the country, in case some loon decided to live the story line.

TV-PG stands for "parental guidance suggested." TV-14 designates that a program is inappropriate for viewers under 14. This change to a tougher rating is surprising, since WB execs are said to have trimmed a bit of the more grisly stuff from the episode. But WB execs said, when the episode was pulled and again when it was rescheduled, they felt it was better to air on the side of caution.

A WB spokesman would only say of the rating change: "We have been very consistent in our approach to this episode. And this rating is another example of our sincerity throughout the entire process."

Expect CBS's "Martial Law" to go to camp next season. The network has hired former "Diagnosis Murder" show-runners Lee Goldberg and Bill Rabkin to oversee the drama series's sophomore season; it stars martial arts expert Sammo Hung as well as Arsenio Hall.

Goldberg and Rabkin achieved the impossible last season--they got the press to write about "Diagnosis Murder." The program, which stars Dick Van Dyke as doc/sleuth Dr. Mark Sloan and his son Barry as Detective Steve Sloan, is the oldest-skewing show on television--and therefore the unhippest, in the minds of reporters.

But Goldberg and Rabkin got their attention with campy story lines like the one they produced for the May sweeps race about the murder of the Pox TV network's star masked magician. Pox (translation: Fox) had shows on its Thursday schedule like "Red Asphalt: America's Bloodiest Car Accidents" and "Maimings, Massacres and Practical Jokes" that were giving the No. 1-ranked show of the UBC (translation: NBC) network, "He's My Wife," a run for its money.

This really tickled several TV critics, who actually wrote about it; it was probably the first time they wrote about "Diagnosis Murder" in years.

Goldberg and Rabkin are likely to do the same for "Martial Law," which got respectable numbers last season but never broke out from the pack. So expect more fish-out-of-water story lines for Sammo and less cop-drama action next season.

Aida Turturro, cousin of actors John and Nick Turturro, has joined the cast of HBO's "The Sopranos," playing the older sister of stressed-out New Jersey mobster Tony Soprano.

It's unclear how Turturro's character, Janice, will be introduced into the drama, which begins its second season in January. There was talk that the story line will find the eldest Soprano daughter returning to the East Coast after some years in California.

The only reference to the older sister in the first 13-episode "Sopranos" season came in the flashback episode "Down Neck," which revealed that Tony had a younger and an older sister. Turturro will be seen on the big screen this summer in Warner Bros.' "Deep Blue Sea" and in Martin Scorsese's fall release "Bringing Out the Dead."