With the Supreme Court verdict of Catalan politicians and activists tried for their part in the 2017 bid to split from Spain likely to rock the political world when it is announced in October, what might come next should they be found guilty is a hot topic in Catalonia.

Charged with rebellion, sedition and misuse of public funds for carrying out the unilateral referendum on October 1, 2017, and the declaration of independence that followed, some of the leaders in preventive detention face prison sentences of up to 25 years.

This week, a Supreme Court prosecutor, Javier Zaragoza, told a radio station in Argentina that as far as he understands the verdict "will come out in the first 10 days [of October], close to the Pilar festival [October 12]." And the expectation is that the leaders will be found guilty.

That scenario would no doubt cause shockwaves in Catalonia that would be felt throughout Spain, which has led to increasingly more voices suggesting either a pardon or an amnesty for the leaders as a way out of the political impasse.

One example is the far-left CUP party, which this week called on the pro-independence camp to join a "major national and international campaign for an amnesty" for the leaders, something the party sees as "the central element" of its political demands.

Amnesty depends on Spanish parliament

The left-wing Catalunya en Comú party of Barcelona mayor, Ada Colau, has also mentioned an amnesty as a possible solution to the crisis, through a change in the criminal law that would see the leaders absolved should they be convicted.

However, Colau's party has avoided taking a hard line on the issue, limiting itself to saying that it is "open to listening to other proposals" and stressing the need for "a negotiated political solution that will get them [the leaders] out of prison."

Meanwhile, the pro-independence Esquerra Republicana Party (ERC), whose leader Oriol Junqueras is one of the jailed leaders, has argued for trying to pass amnesty legislation in the Spanish Congress that would see the prisoners freed.

Pardon within Spanish government powers

Such an initiative would likely fail, as the Socialist, PP and Cs parties, which all oppose independence, would surely vote against the measure. The three unionist parties also rule out a pardon for the leaders, even though it is within the powers of the Spanish government.

Pardoning the leaders should they be convicted is also rejected by the pro-independence parties, even though it would mean their release. The ERC spokesman in Congress said recently: "We will never accept it because it presupposes an acceptance of guilt."

Meanwhile, Junts per Catalunya (JxCat), the party of exiled former president Carles Puigdemont, rules out both a pardon and an amnesty. Its spokesman in Congress recently predicted that "there will never be an amnesty that favors the Catalan political prisoners."

Yet, the idea of an amnesty is out there, and will likely be the subject of discussion in the coming weeks. But while how to respond to a guilty verdict remains unclear, one thing the Catalan parties sympathetic to the jailed leaders agree on is the need for a unified response.

CUP and Catalunya en Comú want to use the parliamentary session on September 25 and 26 to debate a unified strategy, but the government remains tight-lipped on the issue, merely ruling out another referendum or an election as an immediate response to a guilty verdict.