Why did Jar Jar vote to give the Chanceller emergency powers?

As stated in Episode II, Padmé's position as senator was totally against the creation of the Republic's army. She was in the opposition of the voting taking place in the Senate, about this matter.

ANAKIN: As the leader of the opposition, it will be very difficult to get Senator Amidala to leave the Capital.

But, later on, Jar Jar, acting as a Representative fo Naboo, is encouraged to vote for Emergency Powers to the Chanceller, so he could approve the creation of the army. And so he does.

Didn't Jar Jar know about the firm position of Padmé in this matter?

Also

If there was an opposition group, and Padmé was the leader, shouldn't they have advised Jar Jar about this decision?