DETROIT — Emails released in a court case show that General Motors Co. ordered a half-million replacement ignition switches nearly two months before telling the government that its small cars should be recalled because the switches were defective.

The chain of emails between lower-level GM workers and Delphi Corp. shows that GM knew about the deadly switch problem at least as early as Dec. 18, yet it didn’t tell the government of the recall until Feb. 7.

Also, the order was not mentioned when CEO Mary Barra testified before Congress, nor was it discussed in a GM-funded investigation into its conduct by former U.S. Attorney Anton Valukas.

The emails, released Monday by Texas personal injury attorney Robert Hilliard, once again raise questions about what GM knew when, and how forthcoming the company was in congressional testimony and in the Valukas report.