Dennis Ketterer, terminated by Channel 7 last June just a week after he had won a regional Emmy Award as outstanding weathercaster, has sued the station for $12 million, charging discrimination under the D.C. Human Rights Act. He's also seeking reinstatement to his job, claiming breach of contract . . .

The suit, filed Oct. 13 in D.C. Superior Court against WJLA-TV (Channel 7), a division of Allbritton Communications Co., asks $10 million for mental anguish, pain and suffering, emotional distress and humiliation, and an additional $2 million in punitive damages . . .

WJLA president Terry Connelly declined to comment on Friday, saying, "We don't discuss personnel matters." WJLA news director Gary Wordlaw would say only, "Talk to my lawyer." Neither is named in the suit . . .

And Ketterer, who has been studying to obtain a license to sell financial securities since leaving WJLA, said his attorney, Richard D. Heideman, had advised him not to comment . . .

According to the suit, Ketterer, who joined the station as a part-time weather reporter in October 1992, had sought counseling for depression on several occasions following the death of his wife in January 1986 and the death of his father this past January . . .

On or about Feb. 15 of this year, the suit claims, Ketterer was diagnosed by a psychiatrist as suffering from a manic-depressive illness known as bipolar II disorder, for which treatment with lithium was prescribed . . .

Ketterer that same day notified Wordlaw of his "treatable" illness. The news director's "demeanor," according to the suit, "immediately changed from one of caring concern to a reaction of repugnance," and the notification caused a "definite and noticeable change" in Wordlaw's treatment and attitude toward Ketterer . . .

Nevertheless, Ketterer continued as lead meteorologist and weathercaster for the station . . .

A month later, in response to an ongoing request that employees submit ideas and proposals for news stories and series to be aired by the station, Ketterer sent a memo to Wordlaw through the WJLA computer with three story ideas, including one for a three-part series on manic-depressive illness. Ketterer reiterated in the memo, which is attached to the suit, that he had been diagnosed with the illness. In the memo, Ketterer makes no mention of sharing his personal experience with viewers. . .

He also proposed a series on UFOs and a weekly segment on gardening . . .

On March 24, two days after Ketterer had sent the e-mail memo, Wordlaw read it and, according to the suit, ordered him to attend a noon meeting the next day, at which time he was told his employment was terminated, effective June 30 . . .

In late June, he was replaced on the air by Mark Pfister. At the time, the station insisted that Ketterer was in the midst of contract negotiations that probably would mean a role in a revised weekend format due to be introduced Aug. 19 . . .

Ketterer was in the second year of a three-year contract that gave WJLA the option to renew on a yearly basis by June 30 . . .

The suit contends Ketterer was wrongfully terminated although he is a member of a protected class under the D.C. Human Rights Act, in that he suffers a disability as defined in that statute and that the station is also in breach of an implied covenant of good faith and fair dealing for wrongfully accelerating and terminating his contract after it learned of his disability . . .

Heideman is a member of the Heideman Law Group of trial lawyers here and was most recently in the news defending a client in the United Way case. . . "Somebody Say Amen' "

Thursday night continues to be a season-threatening disaster area for ABC. "Murder One," the $30 million courtroom drama the network bought from Steve Bochco to remove some of the clout from NBC's "ER" at 10 o'clock, managed its worst performance yet last week, a 6.7 national Nielsen rating and an 11 percent audience share . . .

"ER," meanwhile, sailed along with a 24.2/40 while even CBS's "48 Hours" beat "Murder One" in the time period with an 8.0/13 (its best so far this young season) . . .

For the entire evening, ABC could do no better than a 5.9/9, compared with a 20.4/33 for NBC, an 8.0/13 for CBS and a 7.0/11 for Fox (over two hours). Worse, if you're in the sales department at one of those networks, "ER" attracted 171 percent more adults 18 to 49 than ABC and CBS combined in that hour . . .

ABC, which won last season's prime-time crown, introduced three hour-long dramas to Thursday this fall, a counter-programming strategy designed to at least take the edge off NBC's overwhelming lineup for that night, which is just strong enough, unless checked, to win the season for NBC. The key to the night, of course, is the 10 o'clock time slot, where "ER" has blown away all competition . . .

Last week, however, ABC was forced to stop production of the other two Thursday dramas, "Charlie Grace" and "The Monroes." Typically, neither helped a bit last Thursday in its farewell appearance. "Grace" did an amazing 6.0/10 at 8, "Monroes" a demure 4.9/8 at 9 . . .

"Murder One," which moved to its Thursday assignment Oct. 12 after three weeks in "NYPD Blue's" Tuesday spot to warm up viewers, has now seen audiences decline for four weeks in a row, after a Sept. 19 debut at 15.5/26. Even last week it drew an 8.3/14 . . .

Nothing can be done about the night until the World Series and then the November sweeps specials (which will undoubtely produce better numbers) are out of the way -- but probably not even then (and what do you do with "Murder One?"). The network did poorly on Thursday last year, but even the News division's magazines performed better than "One," whose latest ratings represent a loss of 8.4 million TV homes in as many appearances over its first five weeks . . .

ABC Entertainment president Ted Harbert wasn't taking calls Friday, but one network source admitted -- for the first time -- "they're studying the options" on Thursday. (FYI on the headline: At the top of Thursday's broadcast, defense attorney Theodore Hoffman -- series star Daniel Benzali -- muttered "somebody say amen,' " which sounds prescient as all hell to me) . . .

Locally, for the evening, the NBC lineup did a 22.1/35 on WRC, compared with a 12.9/20 for Fox on WTTG, a 7.6/12 for CBS on WUSA and a 7.1/10 for ABC on WJLA. "ER" did a 26.5/44, "Murder One" a 10.1/17 and "48 Hours" a 6.7/11. Fox's "N.Y. Undercover" did a 13.4/20 on WTTG. Each national ratings point represents 959,000 TV homes; a local point, 18,836 homes . . .

Tonight starting at 9, C-SPAN will have 90 minutes of live coverage of a black-tie dinner at Union Station honoring former British prime minister Margaret Thatcher. ABC's Barbara Walters will offer welcoming remarks. Also expected to speak during the tribute to Lady Thatcher are Nancy Reagan, former Canadian prime minister Brian Mulroney and Andrew Lloyd Webber . . .

If you care, the latest uproar on the unhappy "Roseanne" set is over; she's back at work, co-star John Goodman is set to continue until this eighth and probably last season is finished, even though he's fed up, and ABC still doesn't want to talk about it . . .

One of the nice people in the network business, Tony Malara, president of affiliate relations for CBS, is leaving as of Dec. 1. He'll be succeeded in that thankless job by Peter K. Schruth, director of sales at WCBS, who gets the title of senior vice president and GM. CBS said Malara, who fought the losing battle against defecting CBS affiliates after the Fox/NFL raid a couple of years back, had planned to leave before the Westinghouse bid for the network. Don't cry for Tony, however: He gets $2.32 million on departure as part of the Westinghouse-CBS deal . . .

TV Guide says "Central Park West" insiders are unhappy with Mariel Hemingway as the leading lady . . .

NBC contract negotiators probably didn't take note, but during the week that Bryant Gumbel missed Tuesday through Friday on the "Today" show -- after being told he wouldn't be on the team for the aborted "interview" with O.J. Simpson -- the morning show somehow managed to score its biggest winning margin over ABC's "Good Morning America" in six years!!! . . .

For the week ending Oct. 13, "Today" did a 4.6 rating and a 21 share, six-tenths of a point over the 4.0/18 for "GMA." The last Pre-Live Audience "CBS This Morning" did a 2.3/10 . . .

Mr. Gumbel's contract is up at the end of November, and with co-anchor Katie Couric due to embark on maternity leave shortly after the holidays, he would still seem to be in the driver's seat on negotiations. However, there are those at the network who are fed up with Gumbel's penchant for taking time off whenever he's displeased with the way things are going in the office, especially at negotiating time . . .

Meanwhile, the bags of fan mail continue to pile up for "Today" news anchor Matt Lauer, who replaced Bryant during the telltale four mornings the week ending Oct. 13 . . .

ABC News reported on Friday that its attorneys have been in touch with a renegade militia group in Garfield County, Mont., trying to negotiate a return of some $66,000 worth of camera and sound equipment seized by the "Freemen" Oct. 2 after six or seven armed men stopped a minivan with three members of an ABC crew for "PrimeTime Live" before escorting them off the outlaw group's property . . .

ABC News said the crew, which "might have included freelancers," thought it was on public property at the time of the confrontation but "nobody was hurt." The three, from Los Angeles, were taping a segment for correspondent Chris Wallace, who was not along at the time. No air date has been set for the "PTL" piece, the network said Friday . . .