Accountability and procedural simplicity. Legislators in a unicameral system are more accountable to the electorate, because the simplicity and directness of the unicameral legislative process encourages citizens to pay attention to legislative activity and permits them to better follow and understand the actions of their representatives. Knowing that they are under more and better scrutiny back home, unicameral legislators naturally feel more accountable and alert to constituent concerns and interests. In a bicameral legislature, on the other hand, accountability is weak, because the complexity of the legislative process discourages and confuses citizens attempting to follow the activities of their representatives so as to hold them to account for their part in legislative decisions.
Accountability and procedural openness. A unicameral legislature is more accountable to the electorate than a bicameral legislature, because the unicameral legislative process is more open to public view. In a unicameral legislature, decisions are made in public settings--either in standing committees or on the floor--where legislators speak and vote in full view of the media and the public. In the bicameral legislative process, in contrast, the fulcrum of legislative decision-making shifts from the standing committees and the floor to negotiations between the two houses--where a few leaders and the members of a few conference committees from each house make the most important legislative decisions in relative privacy and obscurity. Because its pivotal decision-making processes--inter-house negotiations--are so removed from public view and resistant to public comprehension, a bicameral legislature is necessarily less accountable to the voters than a unicameral legislature.
Accountability and the second house. The bicameral structure undermines the accountability of individual legislators by clouding their responsibility for decisions. Legislators in one house can blame decisions on the other house. They can vote for a measure they oppose, or against one they favor, knowing that the other house will reject the result. They are impelled to design legislation not on the merits but rather as ploys to improve their bargaining position with the other house. Members of a unicameral legislature cannot disguise, yield, or distort their decision-making responsibility in these ways. Each member is fully responsible for voting on bills on the floor and can be held to account for those actions by the voters. As a result, citizens are able to fix responsibility for decisions and hold legislators to account for their actions.
* Source: www.house.leg.state.mn.us/hrd/issinfo/ini_bicam.htm