DHS has taken action to address a backlog of potential overstay records we previously identified in April 2011. Specifically, in April 2011, we reported that, as of January 2011, ADIS contained a backlog of 1.6 million potential overstay records, which included prior nonpriority overstay leads that had not been reviewed, nonpriority leads that continued to accrue on a daily basis, and leads generated in error as a result of CBP system changes. DHS uses ADIS to match departure records to arrival records and subsequently close records for individuals with matching arrival and departure records because either (1) the individual departed prior to the end of his or her authorized period of admission and is therefore not an overstay or (2) the individual departed after the end of his or her authorized period of admission and is therefore an out-of-country overstay. Unmatched arrival records—those records in ADIS that do not have corresponding departure records—remain open and indicate that those individuals are potential in-country overstays. To determine whether an unmatched arrival record is likely to be an in-country overstay, DHS agencies review multiple databases to determine if any information is available to document a departure or a change in immigration status. For example, the review process includes both automated searches, such as searching for immigration benefit application information through a U.S. Citizenship and Immigration Services database, and manual searches, such as determining whether the individual applied for refugee or asylum status. provided them to CTCEU for further review and consideration for enforcement action. Table 1 describes how CTCEU resolved these leads. Since completing this review of the backlog of potential overstay records in the summer of 2011, DHS has continued to review all potential overstay records through national security and law enforcement databases to identify potential threats, regardless of whether the subjects of the records meet ICE’s priorities for enforcement action. This occurs on an ongoing basis such that DHS may identify threats among individuals who were not previously identified as such when new information becomes available in various national security and law enforcement databases. As of April 2013, DHS continues to maintain more than 1 million unmatched arrival records in ADIS (that is, arrival records for which ADIS does not have a record of departure or status change). Some of these individuals are overstays, while others have either departed or changed immigration status without an ADIS record of their departure or status change. For example, the individual may have departed via a land port of entry without providing a record of departure or the individual may have applied for immigration benefits using a different name. In addition, these records include those from the previous backlog of unmatched arrival records that were not prioritized for enforcement in the summer of 2011 and have not subsequently been matched against a departure or change of status record. As part of our ongoing work, we are analyzing these data to identify various trends among these unmatched arrival records. For example, our preliminary analysis shows that 44 percent of the unmatched arrival records are nonimmigrants traveling to the United States on a tourist visa, while 43 percent are also tourists but were admitted under the Visa Waiver Program. Figure 1 presents our preliminary analysis of the breakdown of unmatched arrival records by admission class. We also analyzed the records to assess the amount of time that has elapsed since travelers were expected to depart the country, based on travelers’ “admit until” date. CBP assigns certain nonimmigrants an “admit until” date, by which they must leave the country to avoid overstaying. Figure 2 presents our preliminary analysis of the breakdown of the amount of time elapsed, as of November 2012, since the “admit until” date. The average amount of time elapsed for all unmatched arrival records was 2.7 years. As of April 2013, DHS has not analyzed its unmatched arrival records to identify whether there are any trends in these data that could inform the department’s overstay enforcement efforts. We will continue to evaluate these data as part of our ongoing work. Since April 2011, DHS has taken various actions to improve its data on potential overstays. In April 2011, we reported that DHS’s efforts to identify and report on overstays were hindered by unreliable data, and we identified various challenges to DHS’s efforts to identify potential overstays, including the incomplete collection of departure data from nonimmigrants at ports of entry, particularly land ports of entry, and the lack of mechanisms for assessing the quality of leads sent to ICE field offices for investigations. Since that time, DHS has taken action to strengthen its processes for reviewing records to identify potential overstays, including (1) streamlining connections among DHS databases used to identify potential overstays and (2) collecting information from the Canadian government about those exiting the United States and entering Canada through northern land ports of entry. First, DHS has taken steps to enhance connections among its component agencies’ databases used to identify potential overstays and reduce the need for manual exchanges of data. For example: In August 2012, DHS enhanced data sharing between ADIS and IDENT. This improved connection provides additional data to ADIS to improve the matching process based on fingerprint identification. For example, when an individual provides fingerprints as part of an application for immigration benefits from U.S. Citizenship and Immigration Services or a visa from the State Department, or when apprehended by law enforcement, IDENT now sends identity information, including a fingerprint identification number, for that individual to ADIS. This additional source of data is intended to help allow ADIS to more effectively match the individual’s entry record with a change of status, thereby closing out more unmatched arrival records. Beginning in April 2013, ICE’s Student and Exchange Visitor Information System (SEVIS) began automatically sending data to ADIS on a daily basis, allowing ADIS to review SEVIS records against departure records and determine whether student visa holders who have ended their course of study departed in accordance with the terms of their stay. Prior to this date, DHS manually transferred data from SEVIS to ADIS on a weekly basis. According to DHS officials, these exchanges were unreliable because they did not consistently include all SEVIS data—particularly data on “no show” students who failed to begin their approved course of study within 30 days of being admitted into the United States. Also in April 2013, DHS automated the exchange of potential overstay records between ADIS and CBP’s Automated Targeting System (ATS), which is intended to allow DHS to more efficiently (1) transfer data between the systems for the purpose of identifying national security and public safety concerns, and (2) use matching algorithms in ATS that differ from those in ADIS to close additional records for individuals who departed. These changes have resulted in efficiencies in reviewing records for determining possible overstay leads; however, they do not address some of the underlying data quality issues we previously identified, such as incomplete data on departures through land ports of entry. Furthermore, because many of these changes were implemented in April 2013, it is too early to assess their effect on the quality of DHS’s overstay data. Second, DHS is implementing the Beyond the Border initiative to collect additional data to strengthen the identification of potential overstays. In October 2012, DHS and the Canada Border Services Agency began exchanging entry data on travelers crossing the border at selected land ports of entry. Because an entry into Canada constitutes a departure from the United States, DHS will be able to use Canadian entry data as proxies for U.S. departure records. We have previously reported that DHS faces challenges in its ability to identify overstays because of unreliable collection of departure data at land ports of entry. This effort would help address that challenge by providing a new source of data on travelers departing the United States at land ports on the northern border. In the pilot phase, DHS exchanged data with the Canada Border Services Agency on third-country nationals at four of the five largest ports of entry on the northern border. These data covered entries from September 30, 2012, through January 15, 2013. DHS plans to expand this effort to collect data from additional ports of entry and to share data on additional types of travelers. According to DHS officials, after June 30, 2013, DHS plans to exchange data for third-country nationals at all automated ports of entry along the northern border. At that time, DHS also plans to begin using these data for operational purposes (e.g., taking enforcement action against overstays, such as revoking visas or imposing bars on readmission to the country based on the length of time they remained in the country unlawfully). After June 30, 2014, DHS plans to exchange data on all travelers, including U.S. and Canadian citizens, at all automated ports of entry along the northern border. DHS has not reported overstay rates because of concerns about the reliability of its data on overstays. According to federal law, DHS is to submit an annual report to Congress providing numerical estimates of the number of aliens from each country in each nonimmigrant classification who overstayed an authorized period of admission that expired during the fiscal year prior to the year for which the report is made. Since 1994, DHS or its predecessors have not reported annual overstay rates regularly because of its concerns about the reliability of the department’s overstay data. In September 2008, we reported on limitations in overstay data, such as missing data for land departures, that affect the reliability of overstay rates. In April 2011, we reported that DHS officials stated that the department had not reported overstay rates because it had not had sufficient confidence in the quality of its overstay data. DHS officials stated at the time that, as a result, the department could not reliably report overstay estimates in accordance with the statute.