The LeT terrorists had sailed into Mumbai from Karachi and carried out coordinated attacks, killing 166 people and injuring over 300 in November 2008.
"The Mumbai attack case is being tried in an anti-terrorism court in Islamabad since 2009. There has hardly been any such case in any ATC in the country taking more than eight years and still pending. ATC is meant for speedy trial but in this case the ATC is acting like that of sessions court where a case is usually not decided in years," a senior lawyer said.
"It appears that the state is not in hurry to decide this case since the matter is related to its arch rival India," said the lawyer who asked not to be named.
Saeed was released on Thursday, days before the ninth anniversary of the Mumbai terror attacks. The lawyer said that if Pakistan was serious about pursuing this case, it would have been decided years ago.
Pakistan has cited equality of the law for everyone as the basis for releasing the Hafiz Saeed.
Supreme Court Advocate Mobeen Ahmad Qazi said that since this case was being tried in the ATC it should have been decided much earlier. "For that long (eight years) evidence is destroyed in such cases. I wonder why Pakistan is taking too long to decide this criminal case," Mr Qazi said.
The fire-brand cleric had been under detention since January this year. Intelligence agencies say the JuD is the front organisation for the LeT which is responsible for carrying out the Mumbai attack.
The six accused who are still in prison are Abdul Wajid, Mazhar Iqbal, Hamad Amin Sadiq, Shahid Jamil Riaz, Jamil Ahmed and Younis Anjum. The seventh suspect, LeT operations commander Zakiur Rehman Lakhvi, was freed on bail two years ago. He has been living in undisclosed location since then.
India has been demanding Pakistan not only to arrest Saeed and try him in the Mumbai attack case but also punish all those involved in the carnage. India has presented a dossier about Saeed's involvement in the Mumbai attack but Pakistan insists "solid evidence" against him. Pakistan has also asked India to send its 24 witnesses to record their statement.
"The anti-terrorism court Islamabad has recorded the statements of 70 Pakistani witnesses in the case. Now it is up to India to send its 24 witnesses for early disposal of the case," chief prosecutor in the case Chaudhry Azhar said.
A number of Pakistani witnesses, both official and private, have testified and provided evidence against the seven accused, but the Pakistani authorities have been insisting on sending Indian witnesses to Pakistan for reaching a verdict.