LOL. So, if you are not sure is somebody is lying, you can always measure the temperature of the tip of his/her nose!
http://secretariageneral.ugr.es/pages/tablon/*/noticias-canal-ugr/2012/11/22/demuestran-el-aefecto-pinochoa-cuando-una-persona-miente-cambia-la-temperatura-de-la-punta-de-su-nariz