Fazer, acreditar, ou correr atrás de algo errado ou errar o alvo; assumir uma abordagem errada; seguir uma pista errada; acusar ou repreender a pessoa errada.
The police tried to prove Fred was guilty, but they were barking up the wrong tree. He was nowhere near the crime scene.
Don’t focus on the problems. You’re barking up the wrong tree. Focus on the solution.