Blacklisting is the illegal practice of denying employment to individuals on the basis of information, accurate or not, which is held on a database. It has been common in the construction industry, where firms kept lists, often out-of-date or inaccurate, of workers involved in union and political activities and prevented them from working.
Firms who want council contracts must now show they do not practise Blacklisting, and those who have used Blacklisting in the past must prove they have have ceased and taken sufficient measures to remedy their past wrongs.
Any council contractor caught practising Blacklisting in the future will have their contract terminated.
The Council's Procurement Board - the corporate watchdog for major contracts - will scrutinise the process.
Now, council leader Richard Watts will write to the Minister for Local Government to call for a public enquiry into Blacklisting, and also urge London Councils to follow Islington's lead.
Cllr Andy Hull, Islington Council's executive member for Finance and Performance said:
"Blacklisting is an immoral practice that has unfairly caused huge suffering for many workers and their families. We’ve made it clear that we won’t work with firms who Blacklist now, nor with any firms who have Blacklisted in the past and can’t prove they have stopped and made amends.
"We are making a stand against an unfair employment practice that has ruined too many lives and we are challenging the government to hold a public enquiry into this malpractice, which has been widespread.
"It's another way we are making Islington fairer."
The council's Executive agreed the measures last week, following a report on Blacklisting from the Policy and Performance Scrutiny Committee.
Many workers were Blacklisted just for raising completely reasonable health and safety concerns.
Maria Ludkin, GMB National Officer for Legal and Corporate Affairs, said: "GMB welcome this kind of robust governance from local authorities.
"It is the only effective guarantee that blacklisting will be stamped out, and workers who were blacklisted compensated, by companies seeking public sector contracts."