This role is tricky because on one hand, the League has to be all "Don't worry, we're watching out for you" without appearing to be above the people it protects. In a way, the League has to be the sheepdog that lives amongst the flock, not the shepherd that watches over them. Even when saving humanity, the League has to watch itself. "We just saw three people stop a giant the size of a mountain, what will happen if they turn on us?" The League has to perform humanitarian actions on top of its heroic ones, almost distracting the populace from the fact that those seven people could, if they wanted to, likely end civilization as we know it.
But still, there are things that need to be done. If a mad scientist has built a volcano lair deep in the sovereign nation of Markovia and is getting ready to churn out an unstoppable horde of MagmaMen, the League can't just show up and pound the snot out of him. Think of all the diplomatic nastiness around the death of Osama bin Laden - yes, his death is a Good Thing, but the idea that any world figure is just two black helicopters full of hard men away from a watery grave is disquieting.
So the League needs a way to do good, quietly. This is the idea that Batman presents them, the idea that forms The Outsiders (#25/52).
It is also Batman's long con.
So the pitch around the Big Table is like this: We need a group of heroes who are willing get their hands dirty in the best interests of humanity. The League has to maintain a spotless reputation, lest people start think of us as rulers, not heroes. There are things that need to be done in order to save lives that we can't do, so let's form a team on the down-low that can.
Proposed Team Members include:
- Metamorpho - Rex Mason was a young businessman with a bright future until he discovered some illegal dealings on the part of the company he worked for, STAGG. When he tried to turn whistleblower (on the advice of Bruce Wayne, an old school chum), STAGG's founder, CEO, and Rex's father-in-law commissioned a little "accident" involving chemicals (developed in partnership with LexCorp, natch) and an explosion. Metamorpho, The Element Man, was the result, and he stopped at nothing to bring Simon Stagg to justice, even though his quest cost him his wife and family. (Shapechange into elements, stretching, super strength/invulverability)
- Katana - Tatsu Yamashiro is the daughter of one of the many sensei who helped train the man who would become Batman (though she was only a child at the time). Still, the patronage of a young billionaire did wonders for the school and it grew and prospered, so much so that Tatsu's brother developed a taste for the good life. When their father, tired of his son's excesses, tried to disown him, Maseo killed him with the sacred sword Soultaker and took over. Tatsu saw everything and fled with the sword, which is now haunted by the ghosts of those it kills. Cut off from Wayne patronage, Maseo turned the school into a training ground for Yakuza. Tatsu eventually avenged her father's death, but rather than taking her brother's life (and thus being haunted by him), she instead gave him the "to the pain" treatment out of Princess Bride. (Ninja skills, mystical interactions via Soultaker, ability to heal by burning soul energy stored in the sword)
- Terra - Tara Markov was also betrayed by her brother. Brion Markov desired the throne of Markovia, a small city-state on the shores of the Mediterranean (ala Monte Carlo), but his older sister Tara stood in his way. She was aware of his deep gambling debts and how criminals would use said debts to force unsavory things through Markovia's port. She tried to help him free himself of his entanglements, but he failed, always returning to his self-destructive ways. She promised to cut him off once she became queen, so he had his gangland friends "disappear" her onto a cargo ship (human trafficking ala second season The Wire). While crossing the Atlantic she managed to escape her captors and dived overboard, eventually waking up on a small forgotten island where a strange idol granted her powers over rock and stone. As he father still lives, she has yet to bring her brother to justice - it's bad enough that he lost a daughter, must he also lose a son? (Earth bending)
- Technocrat - Geoffrey Barron is seventeen years old and a genius. He's been a genius all his life, constantly tinkering and inventing. A whiz at technology, Geoff was his parents' ticket to the good life, they doted on him, constantly pushing him to achieve more and more. As a minor, Geoff was unable to patent his own inventions, but his father, a community college engineering professor, had no problems do so and taking the credit. When Geoff realized what was going on, and what his inventions were being used for, he cut his parents off from his work and attempted emancipation. They responded by saying he was insane and got him committed to Arkham, then sold his remaining patents to the highest bidder (LexCorp again!) and skipped town. Batman got Geoff out of Arkham after the boy was able to prove he was not (that) crazy. Geoff knows exactly where his parents are and enjoys toying with them, using his computer skills to mess with their ill-obtained lives. (power suit, inventions, hacking, I mean, he's essentially Tony Stark, right?)
- The Yeti - Yeti is from mountains, Yeti come down from mountains when got lost. Yeti met people, nice people, who cared for Yeti, even though Yeti so big and strong. Yeti was happy, never got angry at all anymore. Then soldiers came. They tried to take Yeti. Yeti. Got. Mad. No more soldiers. No more village. No more family. Now Yeti have new family. This time, he will protect them better. (7 foot tall Yeti, becoming 9+ foot tall Hulked out Yeti when enraged)
There's a family theme here with the Outsiders. Each member of the team had to make a Hard Choice (even Yeti, who is not as infantile as he may seem) when it came to those close to them. This is partially because of Batman's own hangups regarding families, but mainly so that the team would easier congeal as a unit, forming a surrogate family bond (Batman got the idea from Terrific's Titans). Batman wants a team that is capable of making hard decisions for the greater good.
He also wants a team that's capable of taking down any member of the Justice League. He'll never voice that opinion (or even think it with all those telepaths running about), but over time, he will guide the team towards facing off against villainous analogs of Justice League members under their Black Ops guise. So Bizarro, Major Force, Nemesis (A Wondy villain I'm making up), Sinestro, Zoom, the rapey Dr. Light, etc will eventually be targets. If called out on it by a member of the Justice League, Bats will just point out that it doesn't do well for their image if people with similar powers as team members are running around committing Bad Acts. The first real test will be when Black Adam eventually turns on the League.
Still, that's a little ways off. Until then, they'll focus on dealing with state-sponsored supercriminals (Egg Fu!) and their own internal struggles with their pasts.