In an open letter published on Saturday, the National Association of Former Border Patrol Officers (NAFBPO) challenged the conventional wisdom that there are just 11 million illegal aliens inside America right now, arguing there are far more than that.

“The National Association of Former Border Patrol Officers (NAFBPO) believes the current estimate of up to 11 million aliens now residing illegally in the U.S. is a gross underestimate,” the organization wrote. “The more likely figure is 18 – 20 million and rising daily.”

They former Border Patrol agents, who remain active in the ongoing discussions regarding immigration and law enforcement through their organization NAFBPO, point back to the 1986 amnesty which had original estimated there were less than a million illegal aliens inside America at the time. As amnesty was implemented, though, it turned out there were closer to 3 million.

“Empirical data collected during processing of 2.7 million persons during the last amnesty established that for every alien estimated to be eligible for amnesty three will actually benefit,” the group wrote. “Even after this incredible failure was discovered, Congress negligently failed to demand a methodology be developed to provide them factual information on the number of individuals who enter and remain illegally in the United States, obviously a willful oversight.”

“Of more serious concern, twenty seven years after the first amnesty was granted, Congress continues to refuse to demand aggressive enforcement of existing Immigration laws while passing more to mollify America,” they continued. “The promise to the American public in 1986 was a lie.”

NAFBPO argues it is “malfeasance in governance and fraud on its face” for members of the U.S. Congress to “even contemplate another amnesty without verification of this basic information.”

“Repeating amnesty using these erroneous calculations again in 2013 presents the real prospect that the United States will immediately be burdened with 30 – 33 million new residents of unknown origin or criminal background,” NAFBPO writes. “That number will then be followed during the next ten years as at least an additional 33,056,946 new immigrants are added to America’s population as a result of passage of S.744.”

NAFBPO adds that it believes existing U.S. infrastructure cannot support the massive influx of new people, either newly legalized illegal aliens or the unprecedented wave of legal immigrants the bill would bring in. “The United States infrastructure cannot withstand such an extreme addition to that number of people taxing our social and criminal justice systems,” NAFBPO wrote. “We don’t need to import or legalize criminals.”

NAFBPO adds that it believes, contrary to the popular political views inside the beltway in Washington, that America’s immigration laws “are not broken.”

“Congress has facilitated them to be ignored and/or abused for political expediency to such an extent that we now face a national security issue involving millions of aliens within our country and others waiting around the world to take advantage of our unwillingness to protect our national sovereignty,” NAFPBPO wrote.