The Uttar Pradesh police on Monday said action should be taken against an Indian Police Service officer for filing a "false" First Information Report against Samajwadi Party patriarch Mulayam Singh Yadav.
IPS officer Amitabh Thakur had filed an FIR against Mr Yadav in July 2015 for allegedly threatening him on the phone.
The UP police in their final report to the court of chief judicial magistrate Anand Prakash Singh said action should be taken against Mr Thakur.
The judge fixed November 15 for passing an order on the police's final report.
Earlier, senior police officer Anil Kumar Yadav had said there was no evidence to prove Mr Yadav had threatened the IPS officer and so a previous final report was approved and the probe was closed.
The IPS officer had questioned a previous final report and sought further investigation into the matter.
The court on August 20, 2016 rejected the final report and directed the police to reinvestigate the matter.
The investigating officer, Anil Kumar Yadav, had collected the Samajwadi Party patriarch's voice samples, though he initially refused to give the samples.
The former chief minister has said he spoke with Mr Thakur to make him understand as an elderly person and did not intend to threaten him. Mr Mulayam alleged that the IPS officer had exaggerated the incident without any reason.