In a letter explaining his opposition to three Senate bills that would outlaw recreational synthetic drugs -- including one written by Minnesota Democrat Amy Klobuchar -- Sen. Rand Paul expressed concerns about increased costs to taxpayers, the spread of radical Islam in federal prisons and congressional overreach.

Klobuchar and two other senators spoke on the Senate floor last week to criticize Paul's effort to stall their bills, which have widespread support from Democrats and Republicans.

Afterwards, a Paul spokeswoman told the Star Tribune that the Kentucky Republican, and son of presidential candidate U.S. Rep. Ron Paul, believes "law enforcement of most drug laws can and should be local and state issues." The spokeswoman also said that Paul's hold does not prevent Senate leaders from bringing the bills up for a vote, but could slow the process.

Law enforcement officials in Minnesota and other states have been calling for congressional action to combat the chemical compounds, which are marketed and sold as bath salts, herbal incense and research chemicals and have been linked to at least one death in Minnesota. A Star Tribune investigation found that the drugs are often marketed as "legal" alternatives to illicit drugs such as cocaine and methamphetamines.

Paul sent the letter to Sen. Chuck Grassley, R-Iowa, and Klobuchar in mid-December. Here are several excerpts:

" ... synthetic drugs are easy to manipulate , there is an almost infinite number of synthetic drugs that can be produced, which makes prohibition difficult to implement."


"… I am concerned about the cost to taxpayers presented by further criminalization. It has been estimated that single marijuana arrest costs taxpayers an average of over $10,000. With federal Bureau of Prisons facilities already operating well above capacity, I am concerned that adding new substances to the list of federally banned drugs will further exacerbate overcrowding problems in our federal prisons. In fact, the United States imprisons more people than any other country in the world. It is even estimated that we imprison half a million more people than communist China."


"The stigma of incarceration can make it practically impossible for many people to find work after they are finally released from prison. In addition, there has been much discussion in the Senate regarding combating radical Islam. Notably, Islam is currently the fastest-growing religion among prisoners in the United States. Sending people – often young people – who may already come from broken homes and difficult family situations into a brutal prison environment is potentially a breeding ground for radicalization."


"Finally, and most importantly, criminalizing drugs on the federal level presents serious constitutional issues. The plain language of our Constitution specifies a very limited number of federal crimes. These include treason, counterfeiting, piracy of felonies on the high seas, offenses against the "laws of nations," or violations of discipline by military or militia personnel."


"Even Justice [Antonin] Scalia recently testified before the Senate Judiciary Committee that he blames Congress for making federal crimes out of too many routine drug cases. He said that he believes this over-criminalization has affected the quality of federal judges, and that federal judges "are not what they used to be," because there are too many judges due to the huge drug caseload."