Certain people can be required to attend court or a police station. In some circumstances a person whose attendance is required at court can be arrested and brought to court if they do not attend even if they are not on bail.
If a person is on bail it is a criminal offence to not turn up to court or the police station on time.1
If a person who has been released on bail fails without a reasonable excuse to attend court or the police station at the time they have been told to, they will be guilty of a separate offence to the one they already face.
A police station is the place that the police are lawfully allowed to hold a person when they take away their freedom, often in a cell. A person can also be questioned at a police station this is called an interview.