Gilbert Levin was involved in the design of the LR experiment and the analysis of the results. For 25 years he has labored to show that the best explanation for the results is that they were produced by Martian organisms. He has collected microbes from Alaska and Antarctica and subjected them to the LR experiments with results that match some of the Viking results. He has experimented with a range of non-biological chemicals see if they can produce the same results. He has questioned assumptions about the absence of liquid water on Mars and the chemical effects of bombardment of the soil by ultraviolet radiation. Levin has made a tremendous contribution to the study of extra-terrestrial life and he has designed new experiments for future Mars missions that could resolve the ambiguous Viking results. Unfortunately his enthusiasm for the issue has put off some scientists who regard his claims about the Viking experiments extravagant and unfounded. Levin has pushed the pendulum towards a biological explanation for the Viking results but, as Klein pointed out, this as a long way from unambiguous evidence of life on Mars.
http://dailynews.yahoo.com/h/space/20010906/sc/viking_data_still_cause_stir_about_mars_life_1.html
