It is considered so serious that the Equality and Human Rights Commission has opened an investigation into it (the EHRC will report in 2020). Initially:
Having received a number of complaints regarding antisemitism in the
Labour Party, we believe the Labour Party may have unlawfully
discriminated against people because of their ethnicity and religious
beliefs.
Our concerns are sufficient for us to consider using our statutory
enforcement powers. As set out in our enforcement policy, we are now
engaging with the Labour Party to give them an opportunity to respond
Then:
We contacted The Labour Party after receiving a number of complaints
about allegations of antisemitism in the party.
We have carefully considered the response we have received from the
Party and have opened a formal investigation.
We are using our powers under the Equality Act to open an
investigation, which will look at:
- whether unlawful acts have been committed by the Party or its employees or agents
- the steps taken by the Party to implement the recommendations made in the reports on antisemitism by Baroness Royall, the Home Affairs
Select Committee and in the Chakrabarti Report
- whether the Rule Book and the Party’s investigatory and disciplinary processes have enabled or could enable it to deal
efficiently and effectively with complaints of race or religion or
belief discrimination and racial harassment or victimisation,
including whether appropriate sanctions have been or could be applied
- whether the Party has responded to complaints of unlawful acts in a lawful, efficient and effective manner
Labour is the first political party to be the subject of a formal EHRC investigation into institutional racism since the inquiry into the neo-Nazi British National Party (probably rather fewer surprises in that report).
The Labour Against Anti-Semitism group claims to have submitted 15,000 pages of evidence that more than a thousand Labour members are anti-semitic and that the party has failed to take proper action.
In an article for the Times titled, "The way in which the leadership of the Labour Party has dealt with anti-Jewish racism is incompatible with the British values of which we are so proud", The Chief Rabbi, Ephraim Mirvis, has also weighed in. No Chief Rabbi has commented on a general election before like this.
In 2016, Parliament's Home Affairs Select Committee ran an inquiry into anti-semitism in the UK and devoted a substantial part of their report to the Labour party. The Committee found "no reliable, empirical evidence to support the notion that there is a higher prevalence of antisemitic attitudes within the Labour Party than any other political party" - indeed it's by no means the worst - but said the leadership's lack of action "risks lending force to allegations that elements of the Labour movement are institutionally antisemitic".
The Committee criticised the Chakrabati Inquiry report into anti-semitism in the Labour party published earlier in the same year, describing it as "compromised", and said Corbyn didn't understand "the distinct nature of post-second-world-war antisemitism".
Clearly, the Labour Leader is not directly responsible for abuse
committed in his name, but we believe that his lack of consistent
leadership on this issue, and his reluctance to separate antisemitism
from other forms of racism, has created what some have referred to as
a ‘safe space’ for those with vile attitudes towards Jewish people.
This situation has been further exacerbated by the Party’s
demonstrable incompetence at dealing with members accused of
antisemitism, as illustrated by the saga involving the suspension,
re-admittance and re-suspension of Jackie Walker. The ongoing
membership of Ken Livingstone, following his outbursts about Hitler
and Zionism, should also have been dealt with more effectively. The
result is that the Labour Party, with its proud history of fighting
racism and promoting equal rights, is seen by some as an unwelcoming
place for Jewish members and activists.
The decision by the Leader of the Labour Party to commission an
independent inquiry into antisemitism was a welcome one,
notwithstanding subsequent criticisms. The Chakrabarti report makes
recommendations about creating a more robust disciplinary process
within the Labour Party, but it is clearly lacking in many areas;
particularly in its failure to differentiate explicitly between racism
and antisemitism. The fact that the report describes occurrences of
antisemitism merely as “unhappy incidents” also suggests that it fails
to appreciate the full gravity of the comments that prompted the
inquiry in the first place. These shortfalls, combined with Ms
Chakrabarti’s decision to join the Labour Party in April and accept a
peerage as a nominee of the Leader of that Party, and her subsequent
appointment as Shadow Attorney General, have thrown into question her
claims (and those of Mr Corbyn) that her inquiry was truly
independent. Ms Chakrabarti has not been sufficiently open with the
Committee about when she was offered her peerage, despite several
attempts to clarify this issue with her. It is disappointing that she
did not foresee that the timing of her elevation to the House of
Lords, alongside a report absolving the Labour Leader of any
responsibility for allegations of increased antisemitism within his
Party, would completely undermine her efforts to address this issue.
It is equally concerning that Mr Corbyn did not consider the damaging
impression likely to be created by this sequence of events.
For an organisation to be institutionally racist, we don't mean that every member is racist or even most members are racist, or that there is intent in the organisation to be racist - it is about outcomes. If the totality of the body's efforts (their complaints, procedures, investigations, disciplinaries etc) or lack of efforts lead to racist outcomes, it's institutionally racist.
"the collective failure of an organisation to provide an appropriate
and professional service to people because of their colour, culture or
ethnic origin", which "can be seen or detected in processes,
attitudes, and behaviour, which amount to discrimination through
unwitting prejudice, ignorance, thoughtlessness, and racist
stereotyping, which disadvantages minority ethnic people." - Sir
William Macpherson
There is a not unfounded perception that Labour has, over time, been very slow to investigate, failed to take action against anti-semitic members, ignored the problem, denied the existence of the problem, doubled down on causing the bad outcomes, blamed the complainants and even driven some of the complainants out of the party.
In April 2019 the Sunday Times published a story headed, "Labour’s hate files expose Jeremy Corbyn’s anti‑semite army" (paywall):
The Labour Party has failed to take disciplinary action against
hundreds of members accused of anti-semitism under Jeremy Corbyn’s
leadership, according to internal documents leaked to The Sunday
Times.
A hard drive of emails and a confidential database last updated on
March 8 reveal how the party’s system for dealing with such complaints
is bedevilled by delays, inaction and interference from the leader’s
office. They reveal members investigated for posting such online
comments as “Heil Hitler”, “F*** the Jews” and “Jews are the problem”
have not been expelled, even though the party received the complaints
a year ago.
The newspaper claimed the leaks showed that more than half of the cases remained unresolved to March 2019 and in 28% of them there had been no investigation.
In July 2019, BBC's Panorama reported in a programme titled “Is Labour Antisemitic?” (iPlayer link) reported among other things that Corbyn’s general secretary Jennie Formby, chief of staff Karie Murphy, director of strategy Seumas Milne and adviser Andrew Murray meddled in what were supposed to be independent investigations, overruling and downgrading penalties. It appeared to be a party concerned with damage control instead of investigating complaints.
Worse, Corbyn himself has often seemed to believe there hasn't been a problem or not cared if there was. He has also shared platforms with anti-semitic people, such as proponents of killing Jews (e.g. Hamas and Hezbollah) and even supported them. I think that in those respects, as in the IRA involvement, Corbyn's political judgment on this has been spectacularly poor for an MP and would-be PM. As the-then Labour Chief Whip said of Corbyn inviting two convicted IRA terrorists to Parliament two weeks after the 1984 Brighton hotel bombing:
I think that, unless you are very very careful, any contact with
people of this sort gives credence to their cause, and unless you are
very careful that can lead to people thinking you are actually
indifferent to the outrage, the suffering, the killing and the maiming
which is the direct consequence of the actions of people who are
terrorists.
Corbyn once supported Blood Libel proponent Raed Salah, for example. Corbyn has denied being aware that such individuals have made antisemitic remarks but their remarks and affiliations have been a matter of public record - he could have looked into the people he was to support or share a platform with. So at best he was utterly careless about who he supported. Here is a timeline of some of his behaviour, some of which beggars belief.