Research

Projects listed below are ongoing. For recent drafts, please contact me at lamattio@bu.edu

For information on my ongoing co-authored projects, please click here

Book Project: “U.S. Attorneys and the President’s Judicial Agenda”

U.S. Attorneys wield tremendous authority as the chief federal law enforcement officers in their districts. As prosecutors for the federal government, U.S. Attorneys make decisions about whether and how to pursue cases which affect individuals—defendants and their families, the victims of crimes, and other stakeholders—as well as the national, shared experience of federal law. U.S. Attorneys exercise their authority with discretion, enjoying considerable freedom over how individual cases will be handled, but not independence. How they gain and whether they keep their jobs depends upon another political actor: the president.  A president could leverage his power to select U.S. Attorneys who will perfectly execute his agenda, effectively guaranteeing politicized, responsive, federal law enforcement. Does this happen in practice? This book answers that question by mapping the consequences of strategically appointing U.S. Attorneys for the president’s policy agenda. By combining newly collected biographical data on over 1,500 U.S. Attorneys with the details of millions of federal criminal cases from 1970 to 2025, this project reveals much about the prospects for political control of federal prosecutors’ offices. Presidents often, but do not always, use their authority to select U.S. Attorneys. Once in office, loyal U.S. Attorneys use their power to pursue cases in policy areas the president prioritizes while decreasing the attention paid to other types of cases. The result is a patchwork system of justice, where law is enforced and experienced differently depending upon who serves as U.S. Attorney and the current president’s judicial agenda.

“Complementary Appointments”

At the federal level, the lion’s share of executive interaction with the judiciary occurs in district courts. Judges–chosen by the president and his predecessors–interact with U.S. Attorneys–also presidential appointees. Do presidents jointly consider the opportunity to appoint a judge and U.S. Attorney to a district, or are the two unrelated? Evaluating presidents’ actual appointment behavior reveals that successful appointment of one type increases demand for the other, suggesting that successful judicial appointments complement U.S. Attorney appointments. Next, we evaluate whether there are actual compounding returns to successful presidential appointments. Data on case filings, case outcomes, U.S. Attorneys, and judicial appointments are combined to show whether a complementary effect of judicial and executive appointments exists. As America’s courtrooms become increasingly populated by the current president’s judicial appointees, more cases consistent with the president’s policy agenda are filed. The government’s success rate, already high, climbs even higher. These findings suggest that presidential demand is justified in practice, and will inform scholars engaged in the study of appointments, judicial independence, and executive power.

“The Proliferation of Criminal Law, Reevaluated”

One influential account of mass incarceration holds that its growth is fueled by the steady proliferation of criminal statutes that enable prosecutors to stack charges and strengthen the government’s position in plea negotiations. Analysis of four million federal criminal cases (1970-2017) finds no evidence for that mechanism: enactment of new federal crimes does not independently predict greater diversity in filing offenses, more charges per defendant, higher plea rates, or longer sentences. The principal effect of new statutes lies elsewhere. New crimes create new defendants; a larger number of distinct individuals enter the system under recently enacted statutes. These cases typically resolve through guilty pleas and result in comparatively short terms of imprisonment. Thus, the expansion of federal criminal law grows the carceral state by drawing additional individuals—often in lower-penalty cases—into the federal system. The implications are clear: curbing mass incarceration will require reforms which address who enters the criminal justice system, not just how long they stay.

“Measuring the President’s Judicial Agenda”
Note: This article describes the methodology used to develop the Agenda as used in the book project described above.

Presidents, constrained by institutional barriers and scarce resources, form policy agendas in order to achieve their goals. Given its visibility and importance, forming and pursuing a legislative policy agenda in Congress has occupied scholars of the presidency for some time. This paper argues that a similar effort should and can be made to study the formation of the president’s judicial policy agenda. The demands of office and judicialization of politics jointly compel the president to interact with courts–both directly and indirectly. I argue that direct interaction is shaped, in part, by a set of institution-specific policy goals termed the president’s “judicial agenda”. Computer-assisted text analysis of presidential rhetoric and hand-coded executive branch publications complement one another to produce an annual summary of the president’s judicial agenda from President Nixon through President Trump. Two types of policies emerge: persistent items which repeat across years (i.e. immigration and civil rights) and unique items which appear on the agenda for a single year or single presidency. The number of items on the judicial agenda has increased over time. In terms of agenda content, presidents tend to resemble their predecessors and successors more than their copartisans.

“Bench Appointments”

This short paper examines the curious mechanism by which district court judges can appoint U.S. Attorneys when the office is vacant— accounting for roughly 10% of appointments between 1970 and 2025. These appointments are permanent until a PAS successor is installed. Sometimes the appointment validates the current non-PAS U.S. Attorney, but not always. Though relatively rare compared with other types of appointments, bench appointments have become more common as the Senate declines to consider nominations. The unresolved legal question of whether the president can remove bench appointees has gained new urgency as unitary executive theory because unitary executive practice.