In order to carry out his massacre at the Washington, D.C., Navy Yard, Aaron Alexis needed a weapon and access to a secure building. With a record of mental health issues and criminal behavior, how'd he get them? In short: by slipping through a lot of cracks of various sizes.

How he got his gun

Even the NRA agrees that people with mental health problems should not be able to get access to firearms. Shortly after the shootings in Newtown, Connecticut, last December, the organization called for increased data collection on those with certain mental conditions.

It seems clear, 24 hours after the fact, that Alexis suffered from some mental health issues. As the AP reported Tuesday, Alexis, a Navy veteran, began treatment for "serious mental issues, including paranoia and a sleep disorder," beginning last month. By then, he'd already purchased the shotgun that he used in Monday's attack.

When firearm dealers in states submit an application for a background check to the FBI, mental health is one of the considerations the agency applies for approval. The guideline is specific: the applicant cannot have been "adjudicated as a mental defective or committed to a mental institution." (Only one percent of rejected applications failed due to this restriction.) Alexis was neither at the time of his application. Not that it necessarily mattered; as The Washington Post reported, the Virginia Tech shooter failed the first part of that test, but since state data wasn't shared with the federal government, he passed a background check. The General Accounting Office calculated that the federal database includes about 2.3 million fewer records than it should.

Alexis' pattern of mental health issues overlaps with his criminal history. In 2004, Alexis was arrested in Seattle after an incident in which he shot out the tires of a car, according to the Seattle Police Department.

Following his arrest, Alexis told detectives he perceived he had been “mocked” by construction workers the morning of the incident and said they had “disrespected him.” Alexis also claimed he had an anger-fueled “blackout,” and could not remember firing his gun at the victims’ vehicle until an hour after the incident.

Alexis received misdemeanor charges of property damage and discharge of a firearm. In 2010, he was arrested again, this time for apparently accidentally firing a bullet into his neighbor's apartment. No charges were filed. The FBI background check only bars those "convicted in any court of a crime punishable by imprisonment for a term exceeding one year" from receiving approval.

The FBI also blocks those who have been dishonorably discharged from the military from getting background check approval. Alexis, despite repeatedly being cited for infractions while he was in the military, was honorably discharged.

That background check was the hardest part of Alexis' gun purchase. He needed to show two forms of ID to the dealer in Lorton, Virginia, and pay five dollars — three more than a state resident would have to pay. The NRA outlines the process for acquiring a firearm, but the Wall Street Journal reported the most important detail.

The law allows a buyer to purchase a long gun – which is a rifle or shotgun – without being a resident of the state where the firearm is bought.

So Alexis got his shotgun. According to the most recent reports, he then took at least one handgun from a law enforcement official at the Navy Yard.

Update, 7:00 p.m.: The New York Times reports that Alexis tried to buy an AR-15, but was prevented from doing so by a Virginia state law barring such purchases from non-residents. 

How he got his clearance

In order to carry out his attack, Alexis needed to gain access to the secure Navy Yard building where it occurred. That wasn't a problem, since he had security clearance allowing him to do so. So how'd he get that?

The Post has a thorough look at a process that may be nearly as porous as the FBI background check system.

[I]nvestigators are evaluating whether an individual is trustworthy — a subjective standard that leaves plenty of room for interpretation. [Office of Personnel Management, which generally reviews security applications,] says that negative information, including arrests, can be mitigated by “recency, seriousness [and] relevance to the position and duties.” Investigators have, on appeal, granted clearances to people with histories of alcoholism, drug use, criminal conduct and significant, delinquent debts.

What's more, Alexis had someone on his side: the firm for which he was consulting. Talking Points Memo looked at The Experts, the company that hired Alexis to do IT work at the Navy Yard. Its CEO, Thomas Hoshko, spoke with the Wall Street Journal, as TPM explains.

Hoshko told the Journal that Alexis had a secret security clearance from 2007 and that it had recently been re-approved. But we also know that the crush of federal contracting that has led to dramatically reduced standards for these background checks and checks themselves are now routinely outsourced to still other contractors.

In retrospect of course, Hoshko wishes he hadn't hired Alexis. He suggested to the Post that he wasn't aware of the killer's criminal record or mental health problems. "If I can find this out just by doing a Google search," he told the paper, "that is sad." According to one report, Alexis' most recent background check this summer included only a traffic violation.

The Guardian's national security reporter Spencer Ackerman put the broader problem more bluntly.

Or: The Experts had little incentive to keep Alexis from getting his clearance renewed, nor, particularly, did the government. So Alexis got his access.