As a leader in a union of health care workers, Ligia Galeano knows firsthand how dangerous it is to organize workers in Colombia. First hitmen killed her union activist sister in 2000, then they came for her.

Scary phone calls warned her she "smelled of formaldehyde" and three armed men broke into her house, but she escaped by hiding in a closet and slipping out disguised as a man.

Ten years have passed and nobody has been convicted for the attacks. More than 90 percent of crimes against labor activists go unsolved in Colombia, the world's most dangerous country for unionists amid a long war on Marxist guerrillas.

Colombia's dreadful record on workers' rights has held up a free trade agreement with the United States for years.

"Here they don't go after anybody. If they are taken to jail they just get a slap on the wrist and are let out later," said Galeano, 55, a public health promoter from Cucuta near the northern border with Venezuela.

Last year 37 unionists were murdered, according to official statistics, a 30 percent increase from 2009 after a decade of improvements that saw union murders fall by 80 percent. The National Labor School, a respected rights monitor, has a higher count of 52 union members killed in 2010.

Things may start to improve finally for organized labor, though, with a new proposal to improve worker protections from President Juan Manuel Santos who wants U.S. approval for the trade pact to consolidate Colombia's economic boom.

A deal signed last month with the United States promises labor safeguards that activists have demanded for years. For example, 95 full-time police will investigate crimes involving union members and more money will go to protect leaders.

Colombia will also reestablish a specialized labor ministry and put stricter controls on worker "cooperatives" promoted by the private sector, which unions say have limited rights to collective bargaining.

Hundreds of new labor inspectors will be trained to ensure the measures are enforced.

"We haven't seen a labor agenda like this in at least 20 years," said Lina Malagon from the Colombian Commision of Jurists, a prominent legal advocacy organization.

Threats Continue
Even Colombian business leaders are publicly praising the plan. Some export sectors, like flowers and textiles, see benefits from duty-free access to U.S. markets, but others fear a flood of cheap American goods will be unfair competition.

"Will this action plan have an impact on costs? Yes. Will certain sectors have to adapt? Yes. ... But this is a push towards modernization that we need," said Luis Carlos Villegas president of ANDI, Colombia's biggest industry chamber.

Union experts say the labor plan is a sharp departure from the policies of Santos' predecessor, Alvaro Uribe.

Uribe is credited with dramatically reducing violence in Colombia by cracking down on leftists insurgents, drug traffickers and right-wing paramilitaries.

Human rights activists, however, accuse Uribe of lumping together labor leaders with leftist guerrillas, leaving them open to attacks. His former intelligence chief went to jail for passing paramilitaries the names of union leaders who were later killed.

Colombia now has the lowest level of union affiliation in Latin America, between 3.4 percent and 5.4 percent.

Some unions like Galeano's, a large organization of health workers known as ANTHOC, are skeptical Santos -- a former hard-liner who served as Uribe's defense minister ' will follow through on the lofty pledges. A thick binder of death threats received this year by its members sits on a shelf in ANTHOC's offices in Bogota.

The action plan negotiated by President Barack Obama's administration with Colombia to address concern about the anti-labor violence has given a number of Democrats the political cover they need to vote for the pact although many remain opposed. The White House plans to send legislation soon to Congress to pass the trade agreement, along with other delayed pacts with Panama and South Korea.