The blaze began in the kitchen of a primary school in the southern Indian town of Kumbakonam when Friday's lunch was being prepared on July 15, 2004.
It then spread to the school's palm-thatched roof, trapping scores of children aged between five and 13 in overcrowded classrooms.
In a hard-hitting report, Justice K Sampath blamed local officials for dishonestly certifying the building as safe, even though three schools and 800 children were crammed "like sardines" into one structure with an obviously unsafe thatched roof.
But the strongest condemnation in the report, obtained by Reuters on Monday, came for the school owner, Pulavar Palanichamy, who used his "vaunted political clout" to circumvent the law.
"Because of his avarice and shady dealings, 94 precious lives have been lost and 18 more will carry marks of the sordid episode for the rest of their lives," it said.
The report said Palanichamy had put two private schools into the same building as a government-aided primary school, part of a scam to pretend more children were attending the state-aided school and claim an inflated government grant.
"He was a manipulator par excellence and he had the education, the municipal and revenue department officials under his thumb"
Probe report on the school owner
"He was a manipulator par excellence and he had the education, the municipal and revenue department officials under his thumb," the report said. "He would defy every law under the sun and get away with it."
Many of the children died in a single large classroom with only one exit when the blazing roof collapsed on them and blocked their way out. Others died of suffocation as they tried to escape down the narrow staircases.
At least 18 survivors were hospitalised with burns.
The inquiry report said the local tahsildar, S Paramasivam, the top bureaucrat for a group of villages, acted "in a most dishonest manner" by granting the school a licence, probably without ever visiting it.
Other officials turned a blind eye, some taking money, including chartered engineer Jayachandran, the report said.
"No honest, upright man would have given a stability certificate, particularly when he came to know more than one school was being run there," it said.
Safety standards are routinely disregarded in India, but the Kumbakonam fire was one of the most shocking disasters in the country's recent history.
Palanichamy was arrested after the fire and charged with criminal negligence causing death.
Eleven other people, including officials Paramasivam and Jayachandran, were also arrested and charged.
All have pleaded not guilty and been released on bail.