DENVER (CBS4)– The man convicted in the deadly Boston Marathon bombings will likely spend his sentence at Supermax in Florence, Colorado.

was convicted on all charges Wednesday in the Boston Marathon bombing by a jury that will now decide whether the 21-year-old should be executed or shown mercy for what his lawyer says was a crime masterminded by his big brother.

Tsarnaev’s lawyer has a record of keeping his clients off death row.

Supermax is a notorious prison built to house the worst of the worst criminals.

“It will slowly drive people insane. In fact, it does drive people insane,” said attorney David Lane of Killmer, Lane and Newman.

Lane believes it’s a done deal that Tsarnaev will be incarcerated in Supermax, also known as ADX.

“I would bet the house he will end up in Supermax and not on death row,” said Lane.

In court on Wednesday, Tsarnaev, the former college student, stood with his hands folded, fidgeted and looked down at the defense table in federal court as he listened to the word “guilty” recited on all 30 counts against him, including conspiracy and deadly use of a weapon of mass destruction. Seventeen of those counts are punishable by death.

The verdict, reached after a day and a half of deliberations, was practically a foregone conclusion, given his lawyer’s startling admission at the trial’s outset that Tsarnaev carried out the terror attack with his now-dead older brother, Tamerlan.

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The defense strategy is to try to save Tsarnaev’s life in the upcoming penalty phase by arguing he fell under Tamerlan’s evil influence. The same jury will decide whether Tsarnaev will be sentenced to death or life in prison.

Supermax is the highest security prison in the nation. It was built 20 years ago to house such notorious criminals as Oklahoma City bomber Terry Nichols and Unabomber Ted Kaczynski.

Tsarnaev would join nearly 500 other inmates in a hopeless existence that Lane calls “torture.”

“This is a hellish nightmare of a prison that Tsarnaev will be heading for,” said Lane.

Lane said Tsarnaev’s life will be spent in isolation with virtually no human contact.

“He will spend 23 hours a day, locked down in his own cell with no other human contact, no communication. He will be let out one hour a day into a caged recreation cell all by himself then he’ll be taken back to his cell,” said Lane.

Tsarnaev would live in a sound-proof cell with an open shower and toilet, controlled by guards. His bed, stool and a desk will be inside the cell. His food would be delivered by guards he’ll never see.

The two shrapnel-packed pressure-cooker bombs that exploded near the finish line on April 15, 2013, killed three spectators and wounded more than 260 other people, turning the traditionally celebratory home stretch of the world-famous race into a scene of carnage and putting the city on edge for days.

“I know a lot of people would opt for the death penalty over life at Supermax,” said Lane.

The sentencing phase could begin as early as Monday.