Hunters who kill endangered wolves say they thought they were shooting coyotes or wild dogs. Endangered whooping cranes look like Sandhill cranes, which aren't even threatened. Under what's called the McKittrick policy, ignorance of the law can be an excuse after all. Now, environmental groups are taking the Justice Department to court because it has declined to prosecute a hunter who said, "I didn't know." That's according to Julie Cart, a Pulitzer Prize-winning reporter for the Los Angeles Times.