Scott Peterson's defense attorney claims prosecutors withheld until just last week important information that could clear his client.
Defense attorney Mark Geragos has filed a motion, asking for sanctions against the prosecution in Peterson's double-murder trial.
Peterson is accused of killing his pregnant wife, Laci, and their unborn son in late December 2002.
Geragos contends authorities ignored other leads and focused solely on Peterson. Peterson claims he was fishing alone on San Francisco Bay the day his wife disappeared.
Prosecutors haven't commented. A sweeping gag order has been issued in the case. The trial is set to begin June 1.