James Edwards, 15, was treating the murder as a joke, District Attorney Jason Hicks told an emotional hearing in Duncan, Oklahoma on Tuesday.
"I believe he is a threat to the community," Mr Hicks said of Edwards.
"He thinks this was a joke."
Edwards and Chancey Luna, 16, were charged with first degree murder and face life in prison if convicted.
They were refused bail.
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Michael Jones, 17, was charged with using a vehicle to facilitate the discharge of a weapon and accessory after the fact of murder in the first degree.
Bail for Jones, who is assisting prosecutors and police, was set at $US1 million ($A1.1 million).
The three will be tried as adults.
They were dressed in orange prison jumpsuits and had their legs shackled during the brief appearance in Stephens County Courthouse.
Edwards and Luna did not show any emotion, but Jones broke down in tears after Mr Hicks said he was looking at a "very, very lengthy prison sentence".
"I didn't pull the trigger," Jones said.
It is Luna who prosecutors believe fired the one shot into the back of Mr Lane, 22, who was jogging along a road in Duncan on Friday.
"The information we have was this was the person who pulled the trigger," the prosecutor said.
Mr Lane was staying with his girlfriend Sarah Harper in Duncan before going back to Oklahoma's East Central University where he majored in finance and was the catcher on the team's baseball team.
The court was told that the three boys spotted Mr Lane jogging, got into a car driven by Jones, drove behind Mr Lane and then Luna shot him in the back.
