Of course it was impossible for Justices Roberts and Alito to sign an opinion that explicitly overturned a prior Supreme Court Ruling. After all these gentlemen had, in their confirmation hearings, piously stated that precedents were sacred and that they would not overrule them (the doctrine of Stare Decisis).
Their actions in the last few decisions have indicated that this was all talk and that they had no intention of conforming to precedent.
These justices lied to get confirmed. On those grounds they should be impeached.
Sent to the New York Times