To replicate our analyses it is necessary to run some custom C++ code to fit the dynamic item response theory model. The details of the Markov chain Monte Carlo estimation algorithm are discussed in our Political Analysis article. These two tar-balls contain the C++ code to replicate the analysis in the Political Analysis article. Constant Ideal Point Model (constant.tar.gz) Dynamic Ideal Point Model (dynamic.tar.gz) The code uses the out-dated Scythe Statistical Library, Version 0.2, which is included in the tar-balls. We have compiled and run this code on Linux and MacOS X workstations using gcc 2.95. To compile and run this code on your system, it is necessary to change the paths in the code as well as in the Makefile. The data in the archives comes from the Supreme Court Data Base. All recodes from the raw data are documented in the article. Because estimation takes place using simulation, it is likely you will get slightly different results between runs and across different platforms. Also, make sure to assess convergence before using the posterior density samples for inference. We are no longer actively supporting this code. As soon as possible we will release code for our dynamic item response theory model that runs on the recently released Scythe Statistical Library, Version 1.0. Please contact us if you would like to be contacted when this code is released.