Mayhew derives from this standard the only secure statistical fact in the book, which is that more of the investigations come from a split power system. Seventy three percent of all of the investigations and probes came from a split power, thus opposing powers are more critical and careful of what the other side is doing. Mayhew tries to link that periods of intense investigations may slow the legislative process, but in times of investigation there is no decreasing trend of legislature passed, nor even an influx of divided party legislation when a president is under fire. This goes back to my criticism that many of Mayhew's conclusions are inconclusive. He uses a two-sweep system that covers a lot of the basic legislature, each sweep having its own set of factors.
Some laws are present in both sweeps and some are only applicable to one or neither.
Between the two sweeps two hundred and sixty seven laws were deemed to be important or significant. The laws are agriculture laws, New Deal Laws, Reganomic laws, Social Security laws, Union laws, and many other forms of laws. In looking at the laws that passed, we see bulk laws like the Truman Fair Deal, or the Johnson Great Society plans, that were pushed through in times of unified party control. In the statistics of history and Congress it may seem to show that party unity is a positive and allows more to be accomplished in the United States, however most of these plans met with opposition and passed by narrow margins. Such examples are the Civil Rights Acts during Eisenhower, The Marshall Plan under Truman, and the War Powers Act from Nixon.