what percent of asylum applicants are big liars?

The Home Office of the United Kingdom, in 2007, stated that 80% of applicants from Cameroon were not credible.
In 2007, the US Embassy in Cameroon wrote a cable which said that 80% of asylum applicants from Cameroon were not credible.
In 2007, the US Embassy in Togo wrote that a "large number" of visa applicants and asylum applicants are liars.
In January 2008, the Assistant Chief Counsel [U.S. government lawyer] said in the hallway that 90% of asylum applicants are liars; that the Judges only deny 60% of the cases; the Judges should deny 90% of them. So, in other words, the government lawyer assumes that any given case has a 90% chance of being fake.
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So, what should the asylum applicant who is telling the truth do?
1. give all originals to the Assistant Chief Counsel three months before trial.
2. Tell his father, mother, and brother to visit the US Embassy in the old country and ask to be interviewed and cross-examined in the old country.