A BLACK MAN IS BRUTALIZED by the police. The case leads to a racially charged trial, in which the officer is acquitted. The police chief draws fire for his department’s relations with the black community and inflames the issue by making comments alienating blacks, gays and other groups, all the while blaming the media for his problems.The Rodney King case? No, “Cop Rock,” Steven Bochco and William Finkelstein’s prescient 1990 ABC series that recently enjoyed an encore run on the Arts & Entertainment network. The Daily Variety review, by yours truly, said, “The TV season’s biggest gamble is also in many ways its most impressive new show and, despite prevailing wisdom, could develop a loyal following. Indeed, it’s hard to imagine watching the premiere of Steven Bochco’s flawed yet fascinating musical drama without being intrigued enough by it to at least come back for a second look.” Wrong, but take home these lovely parting gifts and thanks for playing “You Bet Your Credibility.” The series premiere was largely ignored by viewers and the numbers quickly plummeted to near-single-digit shares, prompting the curtain to fall after 11 episodes, closing, appropriately, with a fat lady singing. Still, a second viewing has reinforced the opinion that “Cop Rock” was very much like that little girl with the curl from the nursery rhyme: When it was good, it was better than anything else on television; when it was bad, it was horrid. The sad part is that since “Cop Rock” there hasn’t been anything to rival the series in terms of ambition and excitement, and there’s certainly nothing in this year’s development crop, as divined thus far, that possesses the same level of risk or derring-do. In fact, early indicators suggest suppliers have taken last year’s generally unspectacular development approach a step further, relying on a variety of star-driven concepts and properties built around stand-up comedians in conventional vehicles to almost the total exclusion of risk-taking fare. If this were a self-help book, it would be titled “Smart Executives, Boring Choices.” Does anyone else recall Brandon Tartikoff’s assertion a few years back that every series on television should be someone’s favorite show? With his penchant for quotable soundbites, even Brandon may not remember, but the statement generated considerable discussion at the time, only to be forgotten when NBC’s fall lineup included “Lifestories” and “Hull High.” Nevertheless, there’s considerable merit in the notion that network TV has to inspire more loyalty from viewers in the face of more than two dozen alternatives in most homes. People may watch cookie-cutter fare like “Getting By” or “Crime & Punishment” if there’s nothing else on, but it’s hardly going to be anyone’s favorite show. Small wonder, then, that schedule stunting and specials have proven so effective in pulling audiences away from regular series: There are simply very few shows that carry with them the stamp of being a must-see program. “Cop Rock” asked the burning question whether viewers were ready for “Hill Street Blues” with a beat, and the answer was a resounding no. Still, just because the public nixes one off-kilter project doesn’t mean that the networks lack the right to keep trying. In fact, failing to test those waters could do in the networks a whole lot faster than a 12 share here and there for gambling on something like “Cop Rock.” FEAR OF FLYING BLIND: “Cop Rock” wasn’t exactly a close renewal call based on its performance, and some of this season’s “quality series,” most notably “I’ll Fly Away” and “Brooklyn Bridge,” have also left their respective networks little choice in that regard thanks to the general disinterest of Nielsen families. Several other shows are on the bubble, however, and with all the pilots out there screaming for attention and a place on the schedule, it’s probably a good time to reflect on some of the shows dropped in recent seasons that, in retrospect, may have been let go prematurely — that is, where the network has been unable to equal or surpass a show’s results with any regularity since it left the schedule. ABC, FOR EXAMPLE, HAS STRUGGLED Tuesdays at 10 p.m. since canceling “thirtysomething,” which endured just four years of angst before breathing its last. Though it was taking a significant dive off ABC’s comedies, the 11.3 rating, 20 share original episodes averaged during the 1990-91 season looks pretty good next to recent results in the same hour for “Going to Extremes” and “Civil Wars”– the latter a more conventional but still laudable and low-rated entry from “Cop Rock” progenitors Bochco and Finkelstein. Ditto for moving “China Beach” out of the 10 p.m. time period Wednesday and subsequently canceling “Equal Justice”– the ensemble legal drama that replaced “Cop Rock,” and a show that deserved another year on the air. Many a Saturday at 10 p.m. CBS has probably missed the 8.4/16 the web averaged last season with “P.S.I. Luv U,” even though the show itself could have been more properly titled “P.S. Low IQ.” The same might be said for series like “Paradise,”"Tour of Duty” and “Jake and the Fatman.” NBC’s mistakes are more daunting in that they’ve lived on elsewhere to vex the network, and even with their older demographic skew (described as “55 to dead” in less charitable circles), series like “Matlock” and “In the Heat of the Night” continue to provide respectable household numbers on ABC and CBS. There are a number of shows that won’t be remembered when next fall’s lineups are announced in May. No one will lament the absence of “Space Rangers” or clamor for the “lost” episodes of “Great Scott.” Not so, however, for series like a “Homefront” or “Quantum Leap,” where the network faces a difficult choice: Settle for mediocrity and maintain the status quo, or gamble on improving a time period and possibly letting the bottom fall out.