Change in selection of Lt. Governor candidates

While this was a law that was recently signed isn't a constitutional amendment necessary to change this?

Gov. Pat Quinn signed legislation on Saturday that requires candidates of the same party to be nominated jointly instead of letting voters pick each nominee separately.

Under the new law, a gubernatorial candidate would select a running mate for the primary election. Voters would either support the pair or reject them over a different team.

The change comes after Illinois Democrats were embarrassed in this year's primary election. Scott Lee Cohen was the nominee for lieutenant governor who had been arrested previously for domestic violence. He was soon pressured into dropping out of the race.

The new law will go into effect on Jan. 1.

I wonder how it even came to be that voters individually selected both the gubernatorial nominee and Lt. Governor nominee? If I recall correctly once upon a time the Gov & Lt. Gov candidates were elected separately in a general election. The at some point the the candidates were nominated separately in a primary, then forced to run as a ticket in the general election. I'm sure the point of this was to insure that both the top two executive officers of Illinois were of the same party, but I'll bet money that this wasn't thought out very well for some reason.

BTW, I wonder how that legislation (or amendment) to eliminate the Lt. Gov. position is going. To be sure I still don't support elimination.

Oh yeah this article was the set-up for today's CapFax question of the day. The question is who should Gov. Quinn and State Sen. Bill Brady have selected for Lt. Governor if they could do it all over again?

ALSO, I posted my question in the comments at CapFax and I got a response:

No, this does not require a Constitutional Amendment. This law changes the election code, which is what lays out the guidelines how nominees are chosen.

Here's another explanation:

Article V.4 of the IL constitution specifically gives the legislature the power to require the two to run together as a team. It amazes me that this wasn’t put into effect after the 1986 debacle with the Fairchild LG candidacy. 

Well I think that shall do it for today's civics lesson!

Crossposted @ Mechanics & Illinoize (for the first time in a long while!)