Terry Nichols (right) is already serving a life sentence

But justices, without comment, let stand a ruling by the Oklahoma Court of Criminal Appeals that Nichols can be tried on 160 counts of first-degree murder.

He faces the death penalty if convicted.

Nichols was a former friend of Timothy McVeigh, who was convicted and executed last June for delivering and detonating the bomb which destroyed the office building, killing 168 people.

A federal jury convicted Nichols in 1997 for conspiracy and involuntary manslaughter for the deaths of eight federal agents in the building.

He is currently serving a life sentence.

Double jeopardy

Prosecutors say the state charges involve different victims than the federal charges.

Nichols's argument that the state prosecution amounted to double jeopardy has already been rejected by the Oklahoma Court of Criminal Appeals.

The next step will be for Nichols to attend a hearing to determine whether enough evidence exists to put him on trial.