On April 8, 1622, the Doge had Antonio Foscarini, then a member of the Senate, arrested. The Senate accused Foscarini, since his time in London a notorious bon vivant, of high treason and conspiracy. Foscarini had been part of the Senate himself since 1620, but was accused of visiting the house of the Spanish ambassador and revealing state secrets to Spain (Sandra Secchi, Antonio Foscarini: Un Patrizio Veneziano del ’600, 1969).
Lady Arundel knew Foscarini from his time in London. Rumours quickly spread that some of the meetings between Foscarini and foreign ambassadors had taken place under her roof at Palazzo Mocenigo. British ambassador, Henry Wotton, strongly advised she leave the city immediately.
Less than two weeks later, on April 20, 1622, the council sentenced Foscarini to death for high treason. The sentence was carried out immediately and the body of the condemned man was hung on the Colonna di S. Todaro in Piazza San Marco that night.
The exact background of the Foscarini affair is unclear. The various interpretations of Foscarini’s execution are discussed by Jonathan Walker (Antonio Foscarini in the City of Crossed Destinies 2004) and Murray Brown (The Myth of Foscarini’s Exoneration 2001).
In Venice there was fear of a Spanish conspiracy and although Foscarini belonged to the parliamentary group loyal to the state, his dealings with Lady Arundels, known as strong sympathizers of Spain, could have compromised him:
“Girolamo Lando, Venetian Ambassador in England, to the Doge and Senate: I have always endeavored to encourage confidential relations with the favorites, and especially with the Earl of Arundel, but indeed in these important times, some of those of the Spanish party cannot be brought to more than ceremonious appearances, though I try to gather even this fruit by reciprocal attentions and in every other way possible. “(Calendar of State Papers Relating to English Affairs in the Archives of Venice 17)
Contrary to the advice of the English ambassador, Lady Arundel stayed and instead asked for an audience with the Senate. Her personal appearance at the Doge’s Palace was widely admired as courageous. While an escape would have come close to an admission of guilt, her poise in front of the seventeen members of the Senate on the day after Foscarini’s execution not only saved the Countess from the anger of the Serenissima, but rehabilitated her completely and throughout Europe (Peter Parolin, The Venetian Theater of Aletheia Talbot , Countess of Arundel 2005).
The Senate acquitted the noblewoman of all suspicions. One of the main witnesses, Gerolamo Vano, who for unknown reasons had received money from the council shortly after Foscarini’s death, was subsequently convicted and executed. On January 16, 1623, the Senate posthumously declared Foscarini to be innocent and sent the news of Foscarini’s belated pardon to all courts.