COLUMBIA, S.C. (AP) - A judge says a friend of Dylann Roof cannot get an unusually tough prison sentence for failing to warn police about Roof's plans to kill black worshippers at a Charleston church.

Prosecutors argued that Joey Meek knew about Roof's desire to start a race war by killing black people inside a church. They said his failure to report his friend's plans beforehand prevented authorities from possibly thwarting the massacre.

Previous Coverage: Joey Meek Writes Apology Letters to Mother Emanuel Victims

Meek's sentencing was postponed last month after prosecutors said he needs a harsher punishment than the 27 to 33 months in federal guidelines to fully account for the horrible nature of Roof's crime.

But U.S. District Judge Richard Gergel said Monday that Meek can only be sentenced for what he did after the slayings.