"The BJP did injustice to him," he said when reporters asked him about Prasad's sentence in the fodder scam.
SP national general-secretary Ramashankar Vidyarthi said in Ballia that Prasad was facing consequences for not joining the BJP bandwagon.
"He is being trapped in a conspiracy by the BJP. Had he joined the BJP, he would not have to suffer jail sentence," he said, adding, "I am sure he will get justice from High Court".
He said it was the need of the hour that all opposition parties unite to defeat the BJP.
Prasad was yesterday sentenced to three-and-a-half years in jail and fined Rs 10 lakh by a special CBI court in Ranchi in a fodder scam case relating to fraudulent withdrawal of Rs 89.27 lakh from the Deoghar treasury 21 years ago.
The punishment was handed down to Prasad, 69, by CBI court judge Shiv Pal Singh through video conferencing, since the RJD leader was lodged in Birsa Munda Central Jail after being convicted in the case on December 23, CBI counsel RakeshPrasad said.