Kashyap's daughter Himanshi (27), who was married to the son of Bahujan Samaj Party Rajya Sabha MP Narendra Kashyap, was found dead with a bullet injury to her head at her Ghaziabad residence on April 6.
The MP, his wife and son Sagar were arrested on dowry death charges.
"None of the lawyers in Ghaziabad are ready to take up my daughter's murder case as they are under pressure from the MP and due to this, I had to get lawyers from Badaun," Kashyap said.
He blamed the MP and his family for the death of his daughter.
Kashyap said he will submit a plea for the custody of his daughter's son.
"I will not let my daughter's child stay with such a family. My lawyers will submit a plea in the Allahabad High Court to adopt my grandson," the former BSP minister said.