Bail bond cosigners play a vital role in the bail bond process for a person. Some bail bonds can be dependent on having one or more cosigners. If the defendant fails to get the required number of cosigners for his or her bail bond, then they ultimately cannot get a bail bond and they cannot bail out of jail.
Cosigners are responsible for seeing that the defendant shows up for court appointments. Whether that is just reminding them with a phone call ahead of time or picking them up and driving them to court, it is up to the cosigner to see they make court. And even if it means they chase after them down the street to bring them to court, then so be it, because if the defendant misses a court appointment, there are repercussions for the defendant themselves, but also some for the cosigner.
However, if the cosigner comes to realize they can no longer trust the defendant to willingly appear in court, or if the cosigner believes it will come to the point of needing to chase them down, then the cosigner is free to withdraw their name as a cosigner. There is no consequence to the cosigner for doing this – except maybe prompting the defendant to get mad at them.