Sleight of hand / Kate Wilhelm.

Enhanced descriptions from Syndetics:

Gregarious Vegas entertainer Wally Lederer hasn't always enjoyed the attention of center stage--something he learned about himself over thirty years ago when he was in the slammer serving time for picking pockets. He claims he's turned his life around, and his lucrative and legitimate showbiz career seems to support this. But will the police believe he's a changed man now that Jay Wilkins, a childhood friend, is accusing him of stealing a valuable artifact? More important, does respected attorney Barbara Holloway believe him when he pleads his case to her?

Wally swears he's innocent. There's no way he would jeopardize years of hard work for the fleeting thrill of minor deception. But when Jay is found murdered, Barbara knows Wally is in serious trouble--the police have named him as their prime suspect.

Barbara begins to "dig up the dirt" and is shocked to learn that Jay's wife is now missing--and that Jay himself was far from being the upstanding businessman he claimed to be. Before long, new evidence points toward an unlikely killer, and Barbara must decide if protecting her client by revealing the truth will destroy another life she means to save.