Gavin Shuker, the Labour MP for Luton South, was speaking after Mr Choudhary (above) was convicted of encouraging people to join a banned organisation - in this case, Islamic State.
He faces prison and is due to be sentenced on 6th September alongside Mohammed Mizanur Rahman (below), who's also been convicted of urging people to join a proscribed group.
Dozens of current and would-be jihadis have been linked to the pair, including Michael Adebolajo and Michael Adebowale, the pair who murdered Fusilier Lee Rugby and the IS executioner Mohammad Emwazi, dubbed by the English media as Jihadi John.
Anjem Choudhary has been expressing Islamist sentiments for several years in public, on social media and even the BBC, however authorities have been unable to pin him down under existing terror laws until he explicitly pledged allegiance to IS in 2014.
Some have said the inability to arrest Choudhary until then shows a problem with existing UK terror laws, while others say current laws already infringe on the principle of free speech too much.
Mr Shuker said on Twitter:
Frankly, kids growing up in my constituency of Luton South will be safer tonight with the jailing of Anjem Choudary. pic.twitter.com/WDwKRwiMGo
— Gavin Shuker (@gavinshuker) August 16, 2016
Commander Dean Haydon, head of the Met Police's counter-terrorism unit, said: "These men have stayed just within the law for many years, but there is no-one within the counter-terrorism world that has any doubts of the influence that they have had, the hate they have spread and the people that they have encouraged to join terrorist organisations.
"Over and over again we have seen people on trial for the most serious offences who have attended lectures or speeches given by these men.
"The oath of allegiance was a turning point for the police - at last we had the evidence that they had stepped over the line and we could prove they supported ISIS."
