"So what were 50 members suspended for? What are they under investigation for by the Labour Party compliance unit?"
I would have though that obvious - even to you - an accusation has been made and is in need of investigation?
I would have been irresponsible to have done otherwise.
No problems with investigations - I wonder how many members of the Tory Party would be under investigation in the unthinkable situation of their having such an enquiry.
The right is the traditional home of Antisemitism (6 million witnesses attest to this fact).
Anti-Semitic Tories were putting together a provisional government for when "Herr Hitler" won the day while the people of Britain were huddled in their air-raid shelters.   
As they say - "home is where the heart is"
"I have said that Labour has a problem with antisemitism, according to many senior members."
Of course you "have to say" that;'s the kind of feller you are.
Apparently you have to produce no proof, that's the kind of feller you are too
Jim Carroll