A more thorough explanation:

fidem facere judici

When someone tries to prove their case in court, they need to convince the judge that their evidence is true. This is called "fidem facere judici" in Latin.

For example, if someone is accused of stealing a bike, they might bring in a witness who saw them riding the bike. The witness would need to convince the judge that they are telling the truth, or "fidem facere judici."

Another example could be if someone is trying to get custody of their child. They might bring in letters from friends and family who can vouch for their parenting skills. The letters would need to convince the judge that the person is a good parent, or "fidem facere judici."