Martian prisons could be built from ice on Mars surface

Food for thought! Pardon my sleight of hand and my facetiousness! 

Instead of capital punishment? No way to escape!

"... More than 5 million cubic kilometers of frozen water exists on or near Mars’s surface, with far more predicted to lie beneath. If the Red Planet’s ice proves obtainable, future astronauts could see themselves living in a world out of Disney’s Frozen, scientists reported here today at the annual meeting of the American Geophysical Union. Through various modeling exercises, the team showed the material could be molded into well-insulated, durable structures that effectively shield earthlings from the Sun’s harmful rays. ..."

Martian cities could be built from ice | Science | AAAS "Astronauts could theoretically harness frozen water on the Red Planet to construct habitats and research stations, new analysis suggests"