That's the new thing. An attorney can now make a typical case easily span more than one year. Jury selection is super combative and is probably more lawyer work than an actual trial. I know of a single murder from 15 months ago, the defense attorney just filed a motion that discovery isn't finished yet. That's all you need. For something like this they probably held years of depositions, multiple medical experts, paid for a duplicate full background check, etc.

“The government revealed it had been surveilling Mr. Saipov and two of his associates for years, recording his conversations with them to gather information about his personal contacts, professional experiences, finances, and potential exposure to ISIS propaganda, violent jihadism, and Islamic extremism,” Saipov’s attorney Andrew Dalak argued in the heavily redacted filing.

Dalak wrote the government must disclose details of the surveillance and any materials pertaining to his client’s alleged connection to ISIS, so the legal team can mount a defense.

https://www.kbzk.com/cnn-national/2019/03/18/nyc-terror-suspect-sayfullo-saipov-wants-access-to-government-surveillance-of-him/