'At the time of the donations, the company was carrying on business. It rented premises and it had a substantial turnover. The Liberal Democrat Party acted in entirely good faith in relation to these donations.'
The party may well have acted in good faith, but a judge decided that Fifth Avenue weren't trading.
Their claims of innocence and due diligence should be enough to hold off prosecutions of party officers for accepting an illegal donation, but the fact remains that the donation is illegal - Fifth Avenue were not trading in the UK. Therefore, under s58(2) of the Political Parties, Elections and Referendums Act 2000, the Electoral Commission can go to a magistrates' court and seek an order requiring forfeiture of the money. No prosecution is required and the standard of proof is that of balance of probabilities - the normal standard for civil actions.
Get that chequebook out, boys and girls!