In criminal matters, the accused are arrested because they may destroy the evidence and hamper the investigation. They are also arrested if they cause threat to the complainant or act in furtherance of additional crime etc., Otherwise why should anybody be arrested. Is it not violation of article 21 of constitution.
Arrest is lost resort, when the driver is not belonging to that place, and it is always better to contact a counsel, as he may advise suitably. (There may be certain other violations also like valid driving license, third party insurance etc., in the accident complaint). One is supposed to produce valid driving license and third party insurance before police and arrest may not be compulsory.