Michael Harris has written some [blog posts][1] on ethical aspects of mathematics.

There is also an [opinion piece][2] by Tom Leinster about ethical questions arising for mathematicians working for intelligence agencies. More on mathematics and mass surveillance can be found [here][3]. 


  [1]: https://mathematicswithoutapologies.wordpress.com/?s=ethics
  [2]: https://www.newscientist.com/article/mg22229660-200-maths-spying-the-quandary-of-working-for-the-spooks/#.U19h0qLwpNQ
  [3]: https://golem.ph.utexas.edu/category/2014/07/math_and_mass_surveillance_a_r.html