The constitutional convention was held in Philladelphia in 1787 and it was a convention with delegates from all the states of the union, except for Pennslvania, that aimed to change the lack f power that the executvie and central power had over the whole union, some states wanted a strong central power, while others didn´t, then they came to the realization of creating the bi-cameral system, where there would be a strong central figure (The president) that would be regulated by the Senates and The House of Representatives.