Baldock was found unresponsive in his cell Monday morning, officials said. The coroner said it appears Baldock died of natural causes.
The coroner said Baldock had gone to the emergency room last week, and when he came back to the detention center, he was placed in an isolation cell.
His body will be sent to the medical examiner’s office on Tuesday for an autopsy.
Baldock and another constable, Mike Wallace, were convicted in June on federal charges related to unreasonable searches and seizures.
On August 13, Baldock entered a guilty plea in federal court to attempted murder of a federal agent.