A significant number of sham marriages have taken place after one of the parties has been issued with a deportation order, the Department of Justice has said. It says the Irish Naturalisation and Immigration Service has reported an increase in such cases.

A spokesman for the department said its position was that marriage “does not of itself negate a deportation order or automatically alter an unlawful immigration status to a lawful one”.

He added: “This is based on existing Irish and European Court of Human Rights jurisprudence. Generally, unless there are particular exceptional circumstances in an individual case, the Minister will not revoke a deportation order solely on the basis that the person concerned has married someone who is lawfully resident in the State.”

The department’s comments came in response to questions arising from a High Court judgment by Mr Justice Richard Humphreys in the case of an Algerian man (45) who married a Hungarian woman following a deportation order.

Mr Justice Humphreys said the State needed to make huge efforts to prevent, root out and revoke bogus marriages that follow deportation orders. Such marriages were a “wearingly predictable feature” of deportation cases, the judge added, and people did not earn the right to stay in Ireland merely by going through a ceremony.

The Garda established Operation Vantage in August 2015 to investigate illegal immigration and identify marriages of convenience. A spokesman for the Garda said there had been 58 arrests made since its establishment and that the operation had been extremely successful.

“Since the inception of Operation Vantage, a notable decrease of notifications of intention to marry have been received between EU and non-EU persons [excluding Irish nationals] compared with previous years,” the spokesman said. There have been 58 arrests relating to offences arising out of Operation Vantage to date. There has been a significant amount of marriage cancellations by the parties involved following inquiries and investigation by Operation Vantage,” the spokesman said.

The Garda initiative was announced following a number of trends including a doubling of the number of asylum applications in 2015.

Applications for residency nearly doubled from 3,230 in 2014 to 5,996 in 2015, due to a large increase from certain Asian countries. For example, applications from Pakistani nationals increased from 683 in 2014 to 1,920 in 2015, while those from Afghan nationals rose from 68 in 2014 to 881 in 2015.

The Garda said that since early 2015, a significant increase of marriages had taken place between EU and non-EU nationals as recorded by the General Register Office.

The Government has passed legislation to change the Civil Registration Act to allow registrars new powers to prevent sham marriages. The Department of Social Protection said it was premature to assess how effective the legislation had been.