"If because of a disqualification a person cannot be chosen as a member of parliament or state legislature, for the same disqualification, he cannot continue as a member of parliament or the state legislature," the court said.
"Parliament does not have the power under Articles 102(1)(e) and 191(1)(e) of the constitution to make different laws for a person to be disqualified for being chosen as a member and for a person to be disqualified for continuing as a member of parliament or the state legislature," said the apex court bench of Justice A.K. Patnaik and Justice S.J. Mukhopadhaya.
"The language of Articles 102(1)(e) and 191(1)(e) of the constitution is such that the disqualification for both a person to be chosen as a member of parliament or the state legislature or for a person to continue as a member of parliament or the state legislature has to be the same."
The judgment would come into effect from Wednesday.
Justice Patnaik said: "Sitting members of parliament and state legislature who have already been convicted for any of the offences... (and) saved from the disqualifications by virtue of sub-section (4) of Section 8 of the Act should not, in our considered opinion, be affected by the declaration now made by us in this judgment."
"This is because the knowledge that sitting members of parliament or state legislatures will no longer be protected by sub-section (4) of Section 8 of the act will be acquired by all concerned only on the date this judgment is pronounced by this court," the court said.
"...if any sitting member of parliament or a state legislature is convicted of any of the offence and by virtue of such conviction and/or sentence suffers the disqualifications after the pronouncement of this judgment, his membership of parliament or the state legislature, as the case may be, will not be saved by subsection (4) of Section 8 of the act which we have by this judgment declared as ultra vires the constitution", the court said.
Subsection 4 of Section 8 of the Representation of the People Act permits an elected representative to continue in the legislature or parliament even after he or she has been convicted of a criminal offence, provided he or she gets a stay on the conviction and sentencing by a higher court.
Under this provision of the Act, such a person can even contest elections after the existing house has been dissolved. However, a similar right to contest an election is not available to a convict who is not a member of a state legislature or parliament.
The court said this while allowing two public interest litigations Lily Thomas and NGO Lok Prahari.
The petitioners said subsection 4 of Section 8 of the Act shielded elected representative with criminal antecedents.