However, in 2010 the director of public prosecutions (DPP), Keir Starmer, issued guidelines saying assistance for compassionate motives to help someone who clearly wanted to die could make prosecution less likely.
Computer experts said the delay in detaining the suspects and seizing computer materials could have allowed them to destroy evidence and make prosecution more difficult.
But, the office said, because the ultra-Orthodox community is "very tight-knit and insular," there is "significant danger" that disclosure would cause victims to withdraw cooperation, making prosecutions "extremely difficult, if not impossible".
It would be better to make such prosecutions less arbitrary by giving them to the international criminal court whose creation America opposes.
Describing the case for reform as "overwhelming", Mr Gove will say: "We need to make sure prosecutions are brought more efficiently, unnecessary procedures are stripped out, information is exchanged by e-mail or conference call rather than in a series of hearings and evidence is served in a timely and effective way.
The two men, who were forced out of their jobs last year, are the first senior executives from Wall Street investment banks to face criminal charges stemming from the credit mess, and the investigation by federal prosecutors based in Brooklyn is likely to become a test case of the government's ability to make successful prosecutions of arcane financial transactions.
A bill is going through parliament to address many of these issues and make prosecution of online abuse easier.
This, they argue, would make prosecution and conviction of terror suspects easier so there would be less need to hold them without charge at home or in prison.
"I don't think this new law alone will make prosecution any easier.
Inspector Cheeseman heralds this as a real breakthrough, which should make prosecution much easier.
