04/04/2015 10:54 BST | Updated 04/06/2015 06:59 BST

Stars Versus Supporting Cast: Reviewing the ITV Leaders' Debate

Like situation comedies, multi-candidate debates follow well-established contours. Each genre hinges upon a diverse cast of characters in which two or three individuals dominate, with the others relegated to supporting-player status. By definition the front-runners get the starring roles, while the fringe candidates pop up as needed to supply one-liners, plot points, and narrative juice. Yet in debates as in sitcoms, it is often the lower-billed names who deliver the most compelling performances.

Such was the case with the April 2 ITV Leaders' Debates, in which politicians from seven British parties took questions from a studio audience, squabbled with each other, and did their best to claim as significant a share of the spotlight as possible. The most interesting characters onstage were not the leaders of the three principal parties, but rather their lesser-known counterparts. The clear winner of the debate, Nicola Sturgeon of the Scottish National Party, triumphed by coming across as the most relaxed, animated, and engaging of the lot. She may not stand a chance of becoming prime minister of the United Kingdom, but Sturgeon definitely schooled her rivals in how to play the game.

The two other women in the debate--Natalie Bennett of the Greens and Leanne Wood of Welsh party Plaid Cymru--displayed differing levels of effectiveness. The charisma-free Bennett gave an amateurish performance, like someone who had accidentally wandered in on her way to a mayoral debate in the hinterlands. Bennett's points may be valid, but they are not easily digested when delivered in a relentless honk. By contrast, Leanne Wood brought a quality to the event that rarely surfaces in televised debates: placidity, the kind that suggests depth rather than vacantness. She may not be politically viable at the national level, but voters in Wales are well served by her passionate and thoughtful advocacy.

In a group debate candidates with little possibility of getting elected hold an obvious advantage: unlike the establishment figures, they face a low threshold of accountability. This is what has made presidential primary debates in the U.S. such a minefield for serious-minded contenders like Mitt Romney, who in 2012 suffered the indignity of having to appear alongside flamboyant performance artists like Herman Cain and Michele Bachmann. Though Romney benefited from looking like the only adult in the room, he also got dragged through ideological mud that he was unable to wash off before the general election.

The seven-way British leaders debate exuded none of the loony-tunes qualities of America's Republican primary debates. About the closest equivalent was Nigel Farage of the United Kingdom Independence Party, who eagerly grabbed the role of contrarian as he pleaded the case against British membership in the European Union. Farage is a type familiar to American voters: the supposed truth-teller, who has a simple solution for every complex problem, if only people were smart enough to listen. As a message-bearer, Farage sounds too much like a carnival barker to seem trustworthy, and over the long haul of the debate he could not withstand his opponents' onslaught of criticism; after two hours this outlier stood even farther outside the mainstream than he did going in. At no point, however, was he anything less than fascinating to watch.

Of the three leading players--incumbent prime minister David Cameron, Ed Miliband of Labour, and Nick Clegg of the Liberal Democrats--Clegg displayed the strongest skill-set, though he could not rekindle his star-is-born aura from the 2010 leaders' debates. Cameron, who insisted on this format in lieu of a one-on-one with Milliband, did not embarrass himself; neither did he appear to make any gains, unless treading water counts as such. Amazingly for a politician at this level, Cameron was the victim of a bad make-up job that left his face glistening throughout the debate. And did none of his handlers think to comb the prime minister's hair before he stepped onto the set?

We can safely say that Ed Miliband and television were not made for each other. On camera the Labour leader displays an odd affect, stilted and unnatural, with a voice utterly lacking in authority. To his media trainers this candidate must present a daunting challenge; considering that Miliband once worked on a television program, it is remarkable how little he has absorbed about the medium's requirements. His lack of fluency was most evident when he would begin to answer an audience questioner by speaking directly to that person for a few seconds, then mechanically shifting to the camera's lens once he had established the obligatory connection. Nor does Miliband have a knack for shoehorning his scripted lines into the discussion organically, as with his transparent attempt to recycle Ronald Reagan's "there you go again" line against Cameron.

Although the debate featured a number of highly watchable exchanges, the clashes did not always play out in a visually logical way, thanks to the random placement of the men and women onstage. In American multi-candidate debates the participants are typically positioned so that the front-runners occupy the prime real estate, clustered together in the middle, while the also-rans get stashed at either end. This allows directors to shoot clean camera angles that emphasize the principals and their interaction. The ITV debate lacked this kind of visual conflict, and only rarely did the confrontations unfold in a way that reflected the real-life struggle for primacy among Cameron, Miliband, and (to a lesser extent) Clegg.

In America debate moderators too easily become targets of criticism, especially when partisans confuse weak performances by candidates with moderator bias. The ITV debate gave no such grounds for grumbling, thanks to the solid delivery of Julie Etchingham, who managed to keep the participants in line without making herself the focus of the debate. Etchingham's use of "thank you" as a euphemism for "please stop talking" proved to be a particularly effective strategy in keeping the discussion on track.

Alas, the ITV debate marks the final chance for British voters to see the leading candidates in simultaneous action, thanks to balking by David Cameron. When Cameron, Miliband, and Clegg meet on BBC's Question Time special on April 30th, it will be in the form of serial interviews, not a genuine debate. After watching the principal party leaders get outfoxed by their rivals on ITV, the absence of additional debates may be the best thing that could happen to them.