Twenty-two-year-old Geovanni Lopez of south suburban Lansing now faces three counts of first degree murder.
Investigators say Lopez gave his weapon to Martin Ybarra and then drove him to 87th and Exchange where Ybarra shot the teens over a gang dispute in February 2009.
Ybarra was arrested just days after the murders.
Prosecutors say police had been looking for Lopez ever since.
Lopez being held on $2.5 million bail.