"Justice Memo to Self: No Gunwalking Allowed." A little late for that, ain't it Eric? How about, "and don't get caught raping or murdering, either"?

Eric Holder, Gunwalker extraordinaire, tells his gang not to get caught walking guns no more. Its bad for business. To get caught, that is.

This just in from CBS: Justice Memo to Self: No Gunwalking Allowed

Anymore. As far as you know.

CBS News has obtained an internal message sent from the Justice Department to Southwest Border US Attorneys last week.

It reads, in part: "We should not design or conduct undercover operations which include guns crossing the border. If we have knowledge that guns are about to cross the border, we must take immediate action to stop the firearms from crossing the border, even if that prematurely terminates or otherwise jeopardizes an investigation."

The proclamation is important because agents from the Bureau of Alcohol, Tobacco and Firearms claim that in recent years, they were ordered to do exactly what the message says should not be done: let thousands of guns "walk" across the border into the hands of Mexican drug cartels in an attempt to gain future intelligence.

A CBS News investigation revealed that numerous ATF agents in Phoenix, Arizona vehemently objected to the gunwalking strategy over the course of a year, saying it was unprecedented and extremely dangerous; but they say they were rebuffed. Some of them believe they were transferred or lost their jobs because of their objections.

Initially, ATF leaders and the Justice Department appeared to deny that any gunwalking ever happened. Then, ATF Special Agent John Dodson spoke to CBS News on camera and gave details of the gunwalking he says he took part in and witnessed "almost daily for months" as part of Operation "Fast and Furious."

The Justice Department touts "Fast and Furious" as a successful counter-trafficking operation that ultimately indicted 20 defendants. However, the round-up of the Fast and Furious defendants whom ATF had been watching for many months only happened after the murder of Border Patrol Agent Brian Terry last December. Two assault rifles that ATF allegedly let "walk" a year before were found at Terry's murder. Hours after Terry was gunned down, police rushed to arrest the suspected trafficker who they knew had purchased the rifles and had been under ATF surveillance for over a year. Shortly thereafter, they arrested other suspects in the case. However, the ATF press conference and indictment in Fast and Furious made no mention their connection to Terry's murder, or that ATF had allegedly watched weapons "walk."

It was Agent Dodson and other insiders who blew the whistle on ATF's connection to the Brian Terry murder case.

Attorney General Eric Holder has now referred the controversy to the Justice Department Inspector General for an investigation. Sen. Charles Grassley (R-Iowa) has asked the investigation be moved to another body, citing conflict of interest. Sen. Grassley's ongoing information requests from ATF and the Justice Department dating back to January have gone unanswered. The House Judiciary Committee has also sent the Justice Department a letter asking for more information. And the government of Mexico has asked for a full briefing from the U.S.

Several insiders reacted to the Justice Department's directive on gunwalking by telling CBS News they found it stunning that the Department is iterating a policy that should go without saying, and should be as intuitive as "don't rape or murder."

When answering questions from Senator Kay Bailey Hutchison (R-TX) last week, Holder said, "The mission of ATF is to stop the flow of guns into Mexico and to people who shouldn't have guns here in the states. ATF has served greatly here and in Mexico... Letting guns 'walk' is not something that is acceptable. Guns are different than drugs or money when we are trying to follow their trail. That is not acceptable. We cannot have a situation where guns are allowed to walk. And I made that clear to the US Attorneys and to the agents in charge of various ATF offices."

All of Sharyl Attkisson's gunwalking reports, blogs, and videos can be found in one place at: cbsnews.com/sharylattkisson