The long-awaited report on allegations of anti-Semitism in the Labour Party is due to be published later.
The Equality and Human Rights Commission (EHRC) has looked at whether unlawful acts took place within the party and its response to complaints.
The Labour leadership under Jeremy Corbyn was accused of tolerating a culture of anti-Jewish prejudice.
But Mr Corbyn has insisted he dealt with the issue and strengthened the party's disciplinary procedures.
Labour has been plagued by accusations of anti-Semitism since 2016, with a number of MPs quitting the party in protest.
The EHRC launched its investigation in May last year after receiving a number of complaints from organisations and individuals, including the Campaign Against Anti-Semitism and the Jewish Labour Movement.
The watchdog said it would focus on two areas:
- Whether unlawful acts had been committed by the party and/or its employees and/or its agents
- Whether the party had responded to complaints of unlawful acts in a lawful, efficient and effective manner
The EHRC was able to request interviews with key figures in the party and had the power to demand access to correspondence, emails and other information.
Labour saw a draft of the EHRC's conclusions in July, but Mr Corbyn's successor as leader - Sir Keir Starmer - said he would not comment until the final report was released.
The party has said it is "committed to cooperating fully with the commission's investigation and implementing its recommendations when the final report is published".
This is a watershed moment for the Labour Party.
The EHRC's report is likely to focus on procedures and process rather than people, but the language is expected to be strong.
There will be a verdict - if only by implication - on Jeremy Corbyn's leadership over the issue, which dogged his time in charge of the party.
For Sir Keir Starmer, there will be both challenges and an opportunity.
He will face difficult decisions on whether to take action against any individuals implicated in the report.
But it will also give him the chance to prove he can deliver on his promise to "tear out the poison" of anti-Semitism by its roots.
After Sir Keir took over the party in April, he said tackling anti-Semitism was his "priority".
The EHRC was set up by the Labour government in 2007 to uphold the principles of the Equality Act and is made up of a large panel of lawyers.
Funded by the Government Equalities Office, it is responsible for safeguarding and enforcing the act and holding organisations, such as businesses and government, to account.