The shadow of To Kill a Mockingbird looms intentionally large over THE COLOR OF LAW (Doubleday). Atticus Finch is quoted at the outset, and protagonist A. Scott Fenney’s mother admonishes him to “be like Atticus. Be a lawyer. Do good.” Quite a display of brass for first-time novelist MARK GIMENEZ . His hero rakes in $750,000 a year as a partner at the Dallas firm of Ford Stevens, but easy street turns bumpy when a federal judge appoints him pro bono counsel to a 23-year-old hooker charged with murder. The victim’s father, a senator, tries to pressure Fenney into railroading the defendant, a wake-up call for the lawyer’s slumbering conscience. Gimenez, a Fort Worth–area lawyer himself, shows some rookie jitters, but The Color of Law is an unbeatable legal thriller with a lot of heart.