Double jeopardy is more than just a legal term in this taut and smart courtroom drama by Edgar Award winner Scottoline. Bennie Rosato, the irrepressible head of an all-female Philadelphia law firm, moves to center stage after playing a supporting role in the author's previous novel, Rough Justice. Bennie's client is tough, manipulative Alice Connolly, charged with murdering her police detective boyfriend, who may or may not have been a drug dealer. Complicating matters is Alice's claim to be Bennie's identical twin sister and to have been visited by their long-lost father. Despite her wrenching emotional reaction to this revelation and her mother's deteriorating health, Bennie puts her personal and professional life on the line, immersing herself in the case. She enlists the aid of her associates, Mary DiNunzio and Judy Carrier, as well as Lou Jacobs, a cantankerous retired cop she hires as an investigator. They discover that a web of corruption may have enveloped the prosecuting attorney and judge who are now trying Alice's case. Scottoline effectively alternates her settings between prison, law office, courtroom and the streets. Readers familiar with her previous work will enjoy the continuing evolution of the characters' relationships. Judy is still the bolder of the two associates, her experiences highlighted this time by an amusing venture into the seamy world of pro boxing. But Mary, until now a timid and reluctant lawyer (""Maybe I could get a job eating""), emerges from her shell. Scottoline falters occasionally by resorting to ethnic stereotypes, particularly in her dialogue, but generally succeeds in creating a brisk, multilayered thriller that plunges Rosato & Associates into a maelstrom of legal, ethical and familial conundrums, culminating in an intricate, dramatic and intense courtroom finale. Agent, Molly Friedrich. Major ad/promo; author tour. (Mar.) FYI: Mistaken Identity is one of the six books excerpted in Diet Coke's marketing campaign.