Texas Promise by Peggy McKenzie

She dreams of marriage. He hungers for justice.

The daughter of a U.S. Marshal, Daisy Bennett has spent her entire life watching her mother worry about a husband who might never come home. She knew that was not the life she wanted for herself, so when her childhood sweetheart finally proposed, she makes him promise he’ll never stand behind a lawman’s badge.
At sixteen, Lucas Armstrong made a promise to his murdered father, and for the last six years, he’s done everything he can to keep that promise and find his killer. But without much to go on, and no authority to act, his chances of bringing someone to justice are slim to none…that is until Marshal Bennett, Daisy’s father, offers him an opportunity of a lifetime. But can he afford to accept?

Can one small promise to the past destroy any hope for the future?