US Supreme Court Justice Sonia Sotomayor voiced alarm Tuesday over the current use of solitary confinement as the court declined to hear a case challenging the practice.

Although she agreed with the decision to not hear this case, the justice expressed her overall concerns about the extreme mental anguish caused by solitary confinement and the denial of any daylight for months or years at a time.

She expanded by raising the Eighth Amendment concerns raised by long-term solitary confinement saying, “A punishment need not leave scars to be cruel and unusual.”

In conclusion, Sotomayor reminded courts and correctional institution to remain vigilant to the constitutional problems that arise by keeping prisons in total isolation:

We are no longer so unaware. Courts and corrections officials must accordingly remain alert to the clear constitutional problems raised by keeping prisoners like Apodaca, Vigil, and Lowe in “near-total isolation” from the living world … in what comes perilously close to a penal tomb.