Portugal

Article 2 states:

The following are not eligible to vote:

• a) Persons who are barred by a sentence that has transited in rem judicatam; 
• b) Persons who are clearly acknowledged to be demented, even if they are not barred by a sentence, when they are committed to a psychiatric establishment or are declared to be demented by a medical board composed of two doctors; 
• c) Persons who are deprived of political rights by a judicial decision that has transited in rem judicatam.

Excerpt from the Assembly of the Republic Electoral Law (1979, last amended 2011)

Article 195, paragraph 1 states:

The Government shall resign upon:…c) The Prime Minister’s death or lasting physical incapacitation…

Article 223, paragraph 2 states:

The Constitutional Court shall also be responsible for:

• (a) Verifying the death and declaring the permanent physical incapacity of the President of the Republic, and verifying cases in which he is temporarily prevented from performing his functions…
• d) For the purpose of Article 124(3), verifying the death and declaring the incapacity to exercise the office of President of the Republic of any candidate therefore…

Excerpts from the Constitution of the Portuguese Republic (1974, last amended 2005)