PONTIAC, Mich. -

In matter-of-fact tones, Ian Zinderman told the court Thursday morning how a few weeks before Bob Cipriano was killed and his wife and son were severely beaten his friend Tucker Cipriano and acquaintance Mitchell "Roderick" Young offered him a 1/3 cut of a robbery and murder that was expected to bring them $3,000.

"That's when they decided they were going to go ahead and kill the family," Zinderman told the court. "They wanted me to dispose of the bodies and drive the getaway car. They wanted to dump them into the Detroit River and weigh them down with barrels of some sort."

Read: Zinderman's testimony

Zinderman said Tucker and Young did not specify a family. However, on the night of April 15, 2012 Zinderman helped Tucker break into his family's garage. They took a check card and a gift card. After smoking K2 spice when the cash was exhausted, the plan became more serious. They would return to the Cipriano home in search of valuables and kill the family.

Zinderman said Young and Tucker outlined what the prosecutor called the "batting order."

"Both of them discussed assignments about who would kill which members of the family. Young was supposed to take the parents and Cipriano was going to take his brothers," Zinderman said.

Zinderman told the court Young had volunteered to kill Tucker's sister, 8-year-old Isabella. That seemed to cool Tucker's enthusiasm for the plan.

"He loved his sister more than anything in the world," said Zinderman.

Prosecutor: Was he as determined to do this after the issue of Isabella came up?

Zinderman: No, I don't think so. He didn't feel comfortable.

Young sat ram-rod straight, occasionally taking notes. Zinderman told the court he told the pair he wasn't interested in participating in the attacks and asked to be dropped at a friend's home where he fell asleep.

When Zinderman awoke hours later he saw Tucker Cipriano washing blood from his clothes.

Zinderman will not be charged for his role in the robbery or for failing to call police. Prosecutors have given him immunity in return for his testimony.

Read: Tucker Cipriano pleads no contest to murdering his father

Tucker Cipriano already has pleaded no contest to murder charges. Young faces life in prison in the murder of Bob Cipriano and his the beatings of his wife and son.