Because I harp endlessly about the need to defeat pizza joints in the NSA’s contact chaining, which might affect the process’ utility for the Tsarnaev brothers, both of whom worked at pizza joints who had weird ties to another pizza joint, I wanted to point to this piece describing the deportation proceedings of Mustafa Ozseferoglu.

Ozseferoglu came to the US from Turkey illegally in 2000 when he was 16, across the Mexican border. He was married to an American and has a son born in this country, Osman, whose health concerns Ozseferoglu has cited in his bid to stay in the country.

Ozseferoglu was interviewed by the FBI in July 2013 and then arrested on immigration charges in September 2013 (at the same time the FBI was going after a bunch of other immigrants with ties to the Tsarnaevs).

Ozseferoglu met Tamerlan through his father, but then worked with him briefly in 2009, during which point they exchanged some number of phone calls — for work purposes, according to Ozseferoglu.

Ozseferoglu came to Anzor for repairs regularly. When Anzor asked him why his cars were so rundown, he told him that he delivers pizza for Boston Pizza Express. Pretty soon after that, Tamerlan applied for the job too.

Boston Pizza Express, has since gone out of business, but in 2009 it was located at 1026 Commonwealth Avenue, near Boston University. Ozseferoglu and Tamerlan worked together for between three weeks and three months, a rough estimate that was scrutinized heavily by the prosecution.

[snip]

In Ozseferoglu’s immigration hearing, the number of phone calls between him and Tamerlan during this period of time were called into question. Kelly says the two contacted each other about 100 times. Ozseferoglu says these calls weren’t illicit, or even personal. The two, he says, were just coordinating pizza deliveries.

“When we’re going on delivery, we take some of the deliveries and we call the other driver,” he explains.

But then Ozseferoglu had more recent conversations about car repair in 2013.

“I was driving on Brighton Ave, turning onto Linden Street in Alston, and I saw Tamerlan with his car, waiting on the light and I was turning,” he says, adding that Tamerlan was with his younger brother. “I say, ‘How’s business?’”

“It was like a few seconds,” he says. “I was in the minivan. I told them that minivan had a transmission problem, and you know, I’m looking to repair that. And that’s when I call and ask—you know, transmission repair,” he says.

He got Tamerlan’s new number, he says, and Tamerlan gave him a recommendation of where to get his car fixed. Anzor had moved back to Dagestan at this point.

Finally, FBI has questioned Ozseferoglu about his girlfriend’s pressure cooker, the explanation for which makes no sense.

“If that pressure cooker was a couple of years old, what was the DVD instruction on how to operate a pressure cooker doing in your trash in 2013?” asks Kelly. He says he disposed of it in a public waste bin and had bought the cooker at Macy’s in 2009. His girlfriend used it to cook beans.

[snip]

Law officers took photos of his girlfriend’s pressure cooker and Ozseferoglu was arrested.

Exactly how federal agents became aware of Ozseferoglu is unclear. Agent Robert Marshal, who testified against Ozseferoglu, says it was because of his phone contacts with Tsarnaev.

But Marshall and Kelly also mention a pressure cooker [sic–I believe this is only the instructions] that Ozseferoglu threw in a public trash bin before the Boston Marathon, along with a few identifying documents. “I believe someone found it and brought it to the Watertown Police. I don’t believe Watertown Police were searching his trash,” Marshall testified.

Exactly why a pressure cooker manual sparked the interest of law enforcement before the Boston Marathon bombing is still unclear.

Now, we’ve been told that the government used the phone dragnet to ID the Tsarnaev’s connections, so it is likely the flurry of calls in 2009 followed by the brief calls not long before the attack sparked their attention.

But I doubt that every single person whom the brothers had conversations with in the 4 years prior to the attacks got a detailed interview. So I suspect they had already identified Ozseferoglu as someone meriting heightened interest.

So I would guess that they IDed him the same way I suspect they IDed two or three apparently innocent people in the Najibullah Zazi investigation: by cross-referencing calls with pressure cooker purchase records (though with Zazi, they collected TATP precursor purchase records). And if Ozseferoglu had bought his pressure cooker around the time he was chatting to Tamerlan regularly, that would heighten the suspicion.

Which leaves just the question of why Watertown cops would have kept his pressure cooker manual turned in before the attack (if that’s what happened — it’s also possible they searched Watertown’s trash).

Watertown. Watertown. This investigation always comes back to Watertown.