Sometimes what drives legislation in Washington is not partisanship or principle but just constituent service.
An example appears to be the Citrus Disease Research and Development Trust Fund Act of 2013. The New York Times has a glancing mention of it in an above-the-fold front-page news article today headlined "Citrus Disease With No Cure is Ravaging Florida's Groves."
The Senate bill is introduced by Senator Bill Nelson, Democrat of Florida, and co-sponsored by Senators Boxer and Feinstein, Democrats of California. The House bill is sponsored by Rep. Vern Buchanan, a Republican, and co-sponsored by 21 Democrats and 19 Republicans — all from the citrus-growing states of Texas, California, Florida, and Arizona.
The bill would take money from the tariff on imported citrus or citrus products (like orange juice or concentrate), which now goes into general government funds, and put it into a special "trust fund" for scientific research on diseases and pests affecting the citrus industry. It also requires the president to notify certain congressional committees before entering into any trade agreements that would reduce the tariffs on imported citrus or citrus products.
It's almost certainly a bad idea from the viewpoint of free trade policy or public finance. Why shouldn't citrus research have to compete with other government-funded research on a cost-benefit basis as opposed to having its own dedicated revenue stream? Why not eliminate the tariff entirely and let consumers choose for themselves between imported or domestically grown fruits, without the government pushing them in one direction or another?