Immigration detention in the context of Illegal immigrant

Illegal immigration is the migration of people into a country in violation of that country's immigration laws, or the continuous residence in a country without the legal right to do so. Illegal immigration tends to be financially upward, with migrants moving from poorer to richer countries. Illegal residence in another country creates the risk of detention, deportation, and other imposed sanctions.

Asylum seekers denied asylum may face impediment to expulsion if the home country refuses to receive the person or if new asylum evidence emerges after the decision. In some cases, these people are considered illegal aliens. In others, they may receive a temporary residence permit, for example regarding the principle of non-refoulement in the International Refugee Convention. The European Court of Human Rights, referring to the European Convention on Human Rights, has shown in a number of indicative judgments that there are enforcement barriers to expulsion to certain countries, for example, due to the risk of torture.

The United States government detains immigrants under the control of Customs and Border Protection (CBP; principally the Border Patrol) and the Immigration and Customs Enforcement (ICE).

According to the Global Detention Project, the United States possesses the largest immigration detention system in the world. As of 2020, ICE detains immigrants in over 200 detention facilities, in state and local jails, in juvenile detention centers, and in shelters. Immigrants may be detained for unlawful entry to the United States, when their claims for asylum are received (and prior to release into the United States by parole), during the process of immigration proceedings, undergoing removal from the country, or if they are subject to mandatory detention.

The use of shackles or restraints on pregnant women is a common practice in prisons and jails in the United States, but also documented in countries including Australia, Great Britain, and Japan. Shackling refers to the use of physical restraints such as handcuffs, leg shackles, and belly chains on parts of an individuals body. The shackling of pregnant women commonly occurs while they are transported within a facility, transported to a hospital, and/or during and after childbirth. In the United States, pregnant migrants may also experience shackling while in immigration detention facilities.

Though medical professionals concur that pregnant women and babies under correctional custody face unique healthcare risks, custody policies often do not address their health and safety needs. Those in carceral facilities typically lack of routine prenatal care and adequate nutrition. There is also a risk of experiencing physical and emotional abuse, mental health issues, and untreated sexually transmitted infections. Specifically, shackling can threaten maternal and child health by increasing risk of falls, blood clots and other conditions.