"The release of such information . . . would likely reveal sensitive details about the breadth and scope of the criminal investigation and pending cases," Cmdr. Mike Kafka, a Navy spokesman, said in a statement.

So far, the Navy has charged five people with crimes - none of them admirals - under military law, charging documents show.

In addition, the Navy said it has determined that 40 people committed misconduct by violating ethics rules or other regulations. Their cases have been handled administratively, meaning they did not involve criminal charges.

In many instances, the Navy was prevented from taking tougher action because the statute of limitations under military law - five years for most felonies - had expired. The oldest matter reviewed so far dated to 1992, while most occurred between 2004 and 2010, according to a Navy official.

The official said the Navy has concluded that about half of those under review - 230 people - were not guilty of misconduct. Some were found to have had little or no contact with Francis. Many others attended dinners or accepted gifts, but the Navy determined that there were extenuating circumstances that excused their actions, said the official, who was authorized to speak only under the condition of anonymity.