When is the president of the Senate allowed to vote on legislative matters?

The president of the senate (which is also the vice-president at the same time) can only vote to break a tie, that is when there is the same number of votes in favour and against: his or her vote decides then.

Explanation:

mesopotamian code of hammurabi

and i think its 1860 b.c. you mean lol

special interest groups must step back and let the process work itself out a representative can amend it at several points in the congressional staffers must do homework and report to the floor on what they 've learned