Judge Karen Marquez-Casillas

FY 2020 - 2025*, Sterling Immigration Court

*data covers the first 11 months of fiscal year 2025

Published Nov 7, 2025

Karen de Lourdes Márquez-Casillas was appointed as an immigration judge to begin hearing cases in May 2024. Judge Márquez-Casillas earned a Bachelor of Arts in Finance in 1998 from the University of Puerto Rico and a Juris Doctor in 2002 from the University of Puerto Rico School of Law. From 2014 to 2024, she served as an assistant chief counsel with the Office of the Principal Legal Advisor, U.S. Immigration and Customs Enforcement, Department of Homeland Security, in various locations, including El Paso, Texas; Miami, Florida; and Washington D.C. From 2012 to 2014, she practiced immigration law in El Paso at the Law Office of Felipe Millan. From 2010 to 2011, she served as the managing attorney for Márquez & Ferrari Law Offices in San Juan, Puerto Rico. From 2007 to 2009, she directed the legal division of ALO Corporation, representing financial institutions in federal and state civil cases and bankruptcy proceedings. From 2003 to 2006, she practiced civil litigation with the Law Offices of Ramos-Diaz, Acevedo & Gonzalez in San Juan, Puerto Rico. In 2003, she worked as in-house counsel for the legal division of Universal Group, Inc. in Guaynabo, Puerto Rico. Judge Márquez-Casillas is a member of the State Bar of Texas.

Deciding Asylum Cases

Detailed data on decisions by Judge Marquez-Casillas were examined for the period covering fiscal years 2020 through the first 11 months of 2025. During this period, court records show that Judge Marquez-Casillas decided 216 asylum claims on their merits. Of these, she granted asylum for 43, granted 0 other types of relief, and denied relief to 173. Converted to percentage terms, Marquez-Casillas denied 80.1 percent and granted 19.9 percent of asylum cases (including forms of relief other than asylum).

Figure 1 provides a comparison of Judge Marquez-Casillas's denial rate each fiscal year over this recent period. (Rates for years with less than 25 decisions are not shown.)

Nationwide Comparisons

Compared to Judge Marquez-Casillas's denial rate of 80.1 percent, Immigration Court judges across the country denied 58.9 percent of asylum claims during this same period. Judges at the Sterling Immigration Court where Judge Marquez-Casillas decided these cases denied asylum 60 percent of the time. See Figure 2.

Judge Marquez-Casillas's asylum grant and denial rates are compared with other judges serving on the same court in this table. Note that when an Immigration Judge serves on more than one court during the same period, separate Immigration Judge reports are created for any Court in which the judge rendered at least 100 asylum decisions.

Why Do Denial Rates Vary Among Judges?

Although denial rates are shaped by each Judge's judicial philosophy, denial rates are also shaped by other factors, such as the types of cases on the Judge's docket, the detained status of immigrant respondents, current immigration policies, and other factors beyond an individual Judge's control. For example, TRAC has previously found that legal representation and the nationality of the asylum seeker are just two factors that appear to impact asylum decision outcomes.

The composition of cases may differ significantly between Immigration Courts in the country. Within a single Court when cases are randomly assigned to judges sitting on that Court, each Judge should have roughly a similar composition of cases given a sufficient number of asylum cases. Then variations in asylum decisions among Judges on the same Immigration Court would appear to reflect, at least in part, the judicial philosophy that the Judge brings to the bench. However, if judges within a Court are assigned to specialized dockets or hearing locations, then case compositions are likely to continue to differ and can contribute to differences in asylum denial rates.

Representation

When asylum seekers are not represented by an attorney, almost all of them (77%) are denied asylum. In contrast, a significantly higher proportion of represented asylum seekers are successful. In the case of Judge Marquez-Casillas, 7.4% were not represented by an attorney. See Figure 3. For the nation as a whole, about 17.1% of asylum seekers are not represented.

Nationality

Asylum seekers are a diverse group. Over one hundred different nationalities had at least one hundred individuals claiming asylum decided during this period. As might be expected, immigration courts located in different parts of the country tend to have proportionately larger shares from some countries than from others. And, given the required legal grounds for a successful asylum claim, asylum seekers from some nations tend to be more successful than others.

The largest group of asylum seekers appearing before Judge Marquez-Casillas came from El Salvador. Individuals from this country made up 20.8% of her caseload. Other nationalities in descending order of frequency appearing before Judge Marquez-Casillas were: Honduras (17.1%), Guatemala (10.2%), Peru (10.2%), Nicaragua (6.0%). See Figure 4.

In the nation as a whole during this same period, major nationalities of asylum seekers, in descending order of frequency, were Honduras (11.2%), Guatemala (11.2%), El Salvador (10.9%), Mexico (8.2%), China (5.2%), Venezuela (5.2%), India (5.1%), Ecuador (4.5%), Nicaragua (4.4%), Colombia (4.4%), Brazil (3.1%), Russia (3.1%), Cuba (2.8%).