A new book published this week charges that Gerry Adams, leader of Sinn Fein and a member of Parliament, set up an Irish Republican Army death squad to execute informers. Adams has long claimed that he was never a member of the IRA, but only of its political party, Sinn Fein. But in A Secret History of the IRA, journalist Ed Maloney says that Adams was an IRA operative in the early 1970s, and that he organized the unit that killed 10 people suspected of being British informers. The book says Adams directly approved the execution of at least one of the victims, Jean McConville, a widow whose 10 young children were left orphans. Adams denied the books charges.