Stain On the Silence by Andrew Taylor

You can run from a guilty conscience, but you can't hide . . . James wasn't much more than a child when he had an affair with Lily. And now, twenty-four years later, Lily confesses to James that their affair led to a daughter, Kate. And Kate desperately needs her father's help: she's wanted for murder. But there is no room for murder in James's life. He has a wife, a good job, a nice house in the country . . . As Kate comes crashing into his world, so she lights the fuse under his ordered life. Because James has also been keeping a secret - a very dark and deadly one...