A reader of my most recent post tried the R code I had written to download the data set of electoral disproportionality from the GitHub repository. However, it didn’t work for them. After entering disproportionality.data <- getURL(url) they got the error message: Error in function (type, msg, asError = TRUE) : SSL certificate problem, verify that the CA cert is OK. Details: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed The Solution The problem seems to be that they didn’t have a certificate from an appropriate signing agent (see the RCurl FAQ page near the bottom) for more information. If you are really interested in SSL verification this page from redhat is a place to look). The solution to this problem is pretty straightforward. As the RCurl FAQ page points out you can use the argument ssl.verifypeer = FALSE to skip certificate verification (effectively a man-in-the-middle attack). So, if you get the above error m...