Before Pilate, Christ proclaims that he "has come into the world, to bear witness to the truth." The Christian is not to "be ashamed then of testifying to our Lord." In situations that require witness to the faith, the Christian must profess it without equivocation, after the example of St. Paul before his judges. We must keep "a clear conscience toward God and toward men."
Source: Catechism of the Catholic Church (Vatican.va)