It's coming from the top. Obama has backed this effort from the start. The White House wants the Burr-Feinstein anti-encryption bill [1]. They've been waiting for it for months and the press keeps asking about it. From the White House Daily Briefing on March 11 [2],
> Q: Can I do the weekly check-in on if you guys have anything to say on the Burr-Feinstein legislation on encryption coming out of the Senate?
> MR. EARNEST: I don’t have anything new -- which is to say we continue to be in touch with Congress, and I continue to be personally skeptical -- more broadly, going beyond just this specific legislation, I continue to be a little skeptical of Congress’s ability to handle such a complicated policy area, given Congress’s recent inability to handle even simple things.
The executive branch is home to the Department of Justice. Maybe that is what you were thinking of? If it makes it easier, when you think about the judicial branch think of judges, and for the executive branch think use power.
In the US, judges adjudicate from the facts presented. Unlike many other legal systems, judges do not investigate. Roughly speaking, the judicial branch of the US Federal government is very small, little more than judges and their clerks. The US Constitution grants it little explicit power and its principle source of political power, declaring laws unconstitutional, was established solely by the Federal physician's own precedent: one day the US Supreme Court started declaring laws unconstitutional.
The US Marshal Service is basically the judiciary's law enforcement branch. Yes, the DEA is also part of the DoJ, but the DEA is a lot more akin to the FBI than the Marshal Service.
Marshals do prisoner security and transport, run the witness protection program, and are the legal enforcers of the court's orders. For instance, when the Supreme Court ordered the integration of Southern schools, it was US Marshals who actually enforced the order and were deployed to escort students into their schoools.
The FBI is technically part of an "elected" branch, but it's nonetheless a semi-autonomous agency not directly accountable to the people who voted for the President. Even the President could be investigated by the FBI. We just have to trust that good people were appointed to this agency, and be ready to fight them in court when not-so-good people make bad decisions.
> Q: Can I do the weekly check-in on if you guys have anything to say on the Burr-Feinstein legislation on encryption coming out of the Senate?
> MR. EARNEST: I don’t have anything new -- which is to say we continue to be in touch with Congress, and I continue to be personally skeptical -- more broadly, going beyond just this specific legislation, I continue to be a little skeptical of Congress’s ability to handle such a complicated policy area, given Congress’s recent inability to handle even simple things.
[1] http://www.politico.com/tipsheets/morning-cybersecurity/2016...
[2] https://www.whitehouse.gov/the-press-office/2016/03/14/press...