The Louisiana Employment Law Letter provides some guidelines on how to handle a reduction in force. A big point:
In most situations, the circumstances that compel a company to reduce its workforce don't arise overnight. And they usually aren't entirely secret. If there's a downturn in the economy, a planned reorganization, or a prospective business deal that will lead to a RIF, there's usually a point at which the company can let employees know (without revealing confidential information or compromising the company's plans) that there may be significant changes affecting the number of jobs or employees.
Employers sometimes fear communicating that type of information, thinking that it could affect productivity, loyalty, and morale. Studies have shown, however, that employees value employers that keep them informed, particularly of developments that could affect their jobs, and that that type of communication actually fosters loyalty and morale (which also affect productivity).
Additionally, employees who know of potential changes are less likely to feel hurt or surprised if they're included in a RIF. Employers can always use tools like retention bonuses or other incentives to keep employees on board -- before or after RIF decisions are announced- -- through a target date.
[Execupundit note: Avoid NETMA; i.e., Nobody Ever Tells Me Anything. Let the word out as soon as possible so people can start to plan.]