Madriani; Paul (Fictitious character), Attorney and client, Trials (Murder) 

In "Undue Influence," Paul Madriani, the brilliant defense attorney readers came to admire in the "New York Times" best-sellers "Compelling Evidence" and "Prime Witness," finds himself in a complex web of murder and deceit--this time within his own family. Paul's wife, Nikki, had died of cancer, leaving him alone to bring up their young daughter, Sarah. On her deathbed, Nikki asked a favor of Paul: that he look after her younger sister, Laurel Vega, who is mired in a bitter child-custody battle her former husband, a powerful state legislator. The two Vegas have brawled in open court for weeks, locking horns over who will be awarded custody of their two teenage children.

When Jack Vega's new, younger wife is found slain execution-style in their opulent home, Laurel Vega becomes a prime suspect. And when physical evidence closes the loop, she is arrested and charged with first-degree murder. Paul, remembering his promise to his wife, has no choice but to take her case.

As he scrambles to mount a defense, Madriani investigates every angle of the murder, and uncovers more than a few skeletons in the Vega family closet. He unearths a dark and enigmatic side of Laurel, an aspect he never knew existed, and with this discovery comes the most chilling question of all: Did Laurel Vega commit murder?