Here are the 10 big developments in the case:
In September 2008, seven officers of the Delhi Police stormed an apartment building in Batla House in Delhi's Jamia Nagar after an alleged tip off that terrorists from the Indian Mujahideen were holed up here.
In the shootout, Delhi encounter specialist Inspector MC Sharma was killed. So were two of the men in the flat.
The Batla House encounter took place just days after 26 people were killed and over 100 injured in five serial blasts in Delhi.
Shahzad Ahmed, according to the police, managed to escape along with another man in the flat, and was caught over a year later in his village in Azamgarh in Uttar Pradesh.
"The verdict proves that the encounter was genuine, I am happy that the Delhi Police was able to prove its case, "said P Chidambaram, who was Home Minister at the time of the controversy.
Congress leader Digvijaya Singh had alleged that the encounter was fake. Reacting to today's verdict, the BJP has demanded an apology from him. Mr Singh said he would not oblige.
The judge, on Thursday, said he had not been given evidence to prove that Shahzad Ahmed is a terrorist, but he also said that his focus was on the killing of the police officer. "For the purpose of decision of this case it hardly matters as to whether accused was affiliated to Indian Mujahideen or not," he said.
Some of those who challenged the encounter said Inspector Sharma had been killed by "inter-departmental rivalry". They cited the fact that he was not wearing a bullet-proof vest while facing men believed to be deadly terrorists.
The judge slammed this lapse and pointed out that two other officers were not armed, "Despite all this, Inspector MC Sharma did not wear any body protection device i.e. bullet-proof jacket," he observed. "It is not clear whether it was merely a misadventure or lack of professionalism in Delhi Police or scarcity of weapons with Delhi Police."
Shahzad Ahmad's lawyer had alleged that he was not in the apartment where the alleged terrorists were located. He will be sentenced on Monday.
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