Maj Kirsten's was a public murder. Good-looking, blonde, Swedish, a tourist, she was found stabbed to death and mutilated in one of Chicago's public parks. That got the headlines, put the pressure on the police as politicians and elected officials demanded an equally public solution. They got it of course: a wino, sleeping rough, arrested and charged. The publicwas reassured. Till the next killing - young, blonde, good-looking, mutilated. And the next - the most public of all. Chicago, sweltering in a heatwave, had become a city hot with fear, crying out for relief. That was when Karen Kovac, young, blonde, good-looking, a police officer, was sent out onto the sweating, heat-soaked streets. A decoy to entice a maniac.