The authors are Jonathan and Faye Kellerman. Their book, "Capital Crimes," consists of two novellas. Here are a couple of commentaries on the effort. First from Bookgasm and then Amazon(Publishers Weekly).
"The first, longest and best of the two procedurals is the inappropriately titled 'My Sister’s Keeper,' in which a feisty, dedicated female California state rep is found dead in her office, practically decapitated by a shotgun blast. The detectives who investigate wonder if her politics — whether public (she was a proponent of stem-cell research) or private (she was a lesbian) – have anything to do with the young woman’s demise. Following a trail whose clues include an STD and more than one right-wing nutjob, they have their answer. And then, just when we think it’s all said and done, the Kellermans throw in an extra delicious twist."
"The second collaboration by bestsellers Jonathan and Faye Kellerman (after Double Homicide) offers two thin novellas that dedicated fans will most appreciate. In the first, My Sister's Keeper, Faye Kellerman's LAPD detective Peter Decker makes an extended cameo role in an inquiry into the murder of an activist lesbian California state representative, Davida Grayson. Grayson, who was the focus of threats from politicians and members of the radical right opposed to her support for stem-cell research, is found shot to death in her Berkeley office; an uninspired pair of local police find that the dead woman's personal relationships, rather than her politics, may have motivated the killer."