A Detroit police officer is accused of knowing about a conspiracy to commit murder, then lying to investigators about it.

A one-man grand jury indictment unsealed Monday lays out charges against Officer Elijah Lately.

Lately is accused of knowing about a plot to murder a witness in another criminal case.

Then he allegedly lied to officers investigating the murder, even warning the suspects to “lay low.”

“The evidence is going to show that this police officer not only had knowledge that a murder was about to take place, but he actively undermined the investigation,” said Wayne County Assistant Prosecutor Robert Moran.

Wayne County judge Timothy Kenny called the accusations “shocking.”

“Not only is it a threat to the community, it’s a threat to the entire court system,” said Kenny, who ordered Lately held on $400,000 bond.

Lately largely stood silent during his arraignment, but friends and family protested his innocence outside the courtroom.

Lately’s attorney, Gerald Evelyn, said his client was blindsided by the charges.

“We’re going to contest them vigorously, and we hope that the process plays out in a way that’s fair,” Evelyn said.