The Minister for Justice, Mr McDowell, is engaged in a "dirty war" on immigrants, using fear and policies of "dubious legality" to intimidate and isolate them, the director of the Irish Council For Civil Liberties (ICCL) has alleged.
Ms Aisling Reidy described the forthcoming citizenship referendum as an "insult to the citizens of Ireland".
Ms Reidy expressed concern that parents of Irish children who are facing deportation have been asked to surrender their children's passports.
She said the ICCL was also worried that work permits were held by employers rather than employees, and that non-nationals were being subjected to dawn raid-style deportations.
"By calling the referendum because of non-nationals giving birth in Ireland, the Government looks to scapegoat non-nationals in the eyes of the Irish public."
A spokesman for the Minister for Justice said the Government "fully accepted our legislation needs modernisation". Residency and citizenship policies here were among the "most liberal in the world".
Ms Reidy said the manner in which families were informed of the State's intention to deport them was deliberately intimidating, with letters from the Department of Justice "written in a threatening way to discourage them from knowing or accessing their rights".
The fact that families facing deportation were not entitled to free legal aid meant many had to borrow large sums.
Pointing to recent mass deportations on specially chartered aircraft, Ms Reidy attacked the style of arrest by members of the Garda National Immigration Bureau.
"These have been characterised by migrants being rounded up in the middle of the night, with no warning given to them of their arrest; mobile phones being taken from the families so they cannot make calls to solicitors or to friends to say good-bye."
She added: "The deportations are of course now also being compounded by illegal unconstitutional threats to the parents of Irish children that they must surrender their children's Irish passports or face arrest."
This was of particular concern given that over 10,000 families, who had applied for residency on the basis of having a child born here, were now in a "legal limbo" as this right was withdrawn by the Department of Justice last year following a Supreme Court ruling.
The Reception and Integration Agency (RIA), under the aegis of the Department of Justice, is criticised for the manner in which it last week told asylum-seekers from the 10 EU accession states they would have to leave their current accommodation by May 1st - throwing people who have not been allowed to work "into potential homelessness and destitution".
