In my understanding, police cannot arrest a person just because the allegations pertain to a cognisable and non-bailable offence; there need to legal necesssity and justification. Moreover, in 498A cases the police are strict instruction except with the express approval of the SP of the District.
To respond police - you have to visit police station. If FIR is filed you have to fight out the case. Now a days there is no arrest for 498 A cases.