(Kristi Kinard Suthamtewakul / via AP) Aaron Alexis (Kristi Kinard Suthamtewakul via Associated Press)

Journalists take refuge in documents and e-mails. These tend to be more reliable than word of mouth or the rantings of an anonymous source. In certain cases, official documents can shield a news outlet against libel claims and the like.

Breaking-news events over the past year, however, have highlighted the risks of relying on communications among government officials. Monday yielded the latest example. In early coverage of the Washington Navy Yard shooting, several outlets peddled the story that the gunman had either carried or acquired or ended up in the vicinity of an AR-15. On Tuesday, a top FBI official issued what was essentially an industry-wide correction, saying that the agency had no “information” that Aaron Alexis had used an AR-15.

Just how mention of the AR-15 leaked into scores of quick-twitch media reports may never be fully explained. An integrity-laden correction from the Associated Press yesterday, however, provides some important detail: “That information was based on federal law enforcement officials who were relying on initial descriptions from the scene and was included in official internal FBI reports summarizing the shooting.”

Unclear from the AP correction is whether it and other news outlets knew at the time of their AR-15 reports that the information was in “official internal FBI reports” or whether they were merely relying on telephonic whispers from anonymous officials. What is clear is that the mass decision to go with the AR-15 thing embarrassed media outlets from Fox News through CNN through numerous print outlets. In a segment last night on Fox News, host Bill O’Reilly sniffed out a liberal media conspiracy for having put out the bogus information and proceeding to “celebrate” it in a campaign for gun-control restrictions.

The “official internal FBI reports” summon an echo from the reporting on the Newtown, Conn., massacre. In the chaotic moments following that shooting, news outlets reported that the suspect was Ryan Lanza, not his brother, Adam Lanza, the actual perpetrator. NBC News was among a number of outlets to screw up that detail, and it provided this explanation as to the background. “Law enforcement officials initially told NBC News that the gunman was Lanza’s brother, Ryan, and they had sent out a bulletin to local and federal law enforcement agencies to that effect.” An internal report, in other words.

A third example stretches the trend just a smidgen. Following the Boston Marathon bombings, the New York Post published that horrible cover depicting two innocent men hanging out at the Boston Marathon. “Bag Men,” blared the headline on the page. “Feds seek these two pictured at Boston Marathon.”

On what evidence did the Post rely for that potentially libelous piece of newspapering? “[P]hotos being distributed by law-enforcement officials among themselves.”

Media outlets cite these bulletins and internal communications because they’re evidence of real reporting. If some cop, after all, went to the trouble of putting something in an internal report, then it must be newsworthy, right?

Not at all. There’s nothing authoritative, as we’ve learned to our great regret, in initial police communications. So saying, hey, the police were including this allegation in their internal report doesn’t justify publishing the information.

The law even recognizes this distinction. Under the “fair report privilege,” journalists in covered states may pass along information in government documents even when it defames someone. Not just any government document qualifies, however. According to the Digital Media Law Project, here’s a list of instances in which the privilege wouldn’t likely not be extended:

*Statements made by an arresting officer about the facts of the case, where those facts are not recorded in the police report
*Gossip overheard on the courthouse steps
*Offhand remarks made by a government official in a private setting
*Statements made in a draft government report

The official communications cited in the three examples above probably wouldn’t even qualify as a draft government report. These bulletins are flimsy stuff — proof that “law enforcement sources” right after catastrophic crimes are barely more informed than the oft-ridiculed correspondents babbling into microphones about police vehicles and hovering helicopters.