A national fact-finding and prosecuting authority, the Institute of National Remembrance (IPN), will collect all the statements, investigate each case individually and prosecute anyone who spied or is found to be lying.
Employers will need to verify staff have been vetted and millions of documents from the communist state security apparatus that ran Poland for four decades after world war two will be available for scrutiny by the press.
Making a false statement will be a crime punishable with a ban from public life of up to 10 years - a term that would mean many Poles could never work again in their chosen profession.
"Poland needs this law," Janusz Kurtyka, the IPN chief said.
"The country is still in the process of leaving the communist period behind and tackling the long-term social and political effects of the dictatorship."
No one doubts that the law, which will replace another one that focused on senior officials and politicians, will trace some of those who worked for the former communist government.
Many Poles approve of the principle of vetting, seeing it as an essential cleansing process that was not carried out immediately after communism because of the pressing need for national reconciliation and reconstruction.
The ruling conservative Law and Justice party, led by Jarolsaw Kaczynski, the country's prime minister, says parts of the former communist spy network still have influence in Poland.
Corruption and cryonism
The party blames this network for widespread corruption and cronyism.
But critics complain the law will punish many unlucky ordinary men and women who may have been blackmailed into collaborating rather than the spymasters who ran them.
Kurtyka rejects such criticism, saying the spy network that enforced the power of the communist system needs to be exposed.
"The secret police were absolutely ruthless"
"Even those people who were forced to collaborate with the communist secret services did huge harm to many others," he said.
"The secret police were absolutely ruthless."
Some Poles say the net is being cast too wide, particularly when it draws in lower-ranking officials and those outside the political sphere such as academics and journalists, many of whom say they will refuse to take part in the process.
The new law will involve so many people, at least 300,000 individuals, according to Andrzej Arseniuk, the IPN spokesman, and so much paperwork, that officials say it could take at least a decade to process all the cases.