Statutes 'foster alienation and marginalization against LGBT people'
Margarette May Macaulay made comments during Dec. 5 hearing in D.C.
Barbados march was 'incident free event'
Inter-American Commission of Human Rights held hearing last month
Supreme Court heard two lawsuits this year
Violence, discrimination remain pervasive in the region
Karla Avelar co-founded COMCAVIS in 2008
Advocates criticized government's response, impunity
Gay man attacked in Santiago park on March 2, 2012
Bachelet reaffirms pledge to introduce measure this year