Upset with what they say is the federal government's failure to prosecute illegal immigrants, the entire 19-member California Republican congressional delegation has asked the U.S. attorney general for a meeting to discuss the matter.

In an Oct. 20 letter to Attorney General Alberto Gonzalez, the Congress members also criticized the U.S. attorney's office in San Diego for what they called its "lax prosecutorial standard" of only prosecuting those illegal immigrants with two felony convictions in the San Diego District.

"We write to request a meeting with you to discuss our frustration with the current policies within the Administration related to the prosecution of criminal aliens," the letter states.

The letter goes on to say that too often, illegal immigrants who should be jailed instead benefit from "the current practice of 'catch and release.' "

The Republicans' letter to Gonzalez appeared to be the latest sign of a growing level of conservative Republican frustration with the Bush administration on several issues, including what they say is its failure to enforce the country's immigration laws.

Last week, nearly one-third of the House's 231 Republican members sent a letter to President Bush, saying that if he expects to get their support for a temporary guest worker program, he first needs to clamp down on illegal immigration by strengthening the nation's borders and enforcing immigration laws.

Reached by phone in Washington on Wednesday, U.S. Rep. Darrell Issa, R-Vista —— one of the signatories of the letter —— said that he and other Republican members of Congress took a more diplomatic approach with the Bush administration until late 2004.

"Before the president was re-elected, all of us felt what we had to say had to be said behind the scenes —— and it was," Issa said.

Not anymore.

"All of us realized two things: one, the president had three years (left in office) and (two) we needed for him to use those three years to solve this problem," Issa said.

The federal government has been promising to get a handle on illegal immigration for the last decade, he added. That is what is driving Republicans to step up the pressure on the administration, Issa said.

"We don't have any credibility with our voters," he said.

In the letter to Gonzalez, Issa cited what he said were two particularly egregious examples of failure to prosecute by the San Diego U.S. attorney's office. In one case, he said, an undocumented immigrant had previously been convicted of narcotics charges on "at least two occasions." And yet, Issa alleged, he was told by officials with the San Diego office that they had decided not to prosecute the man, who was recently apprehended by the U.S. Border Patrol and remains in custody.

Officials with the U.S. attorney's office did not return phone calls for comment Wednesday.

However, in earlier interviews, officials there have said that they are limited in the number of human smuggling cases they are able to prosecute because of a lack of funding.

Citing another case, Issa wrote to the attorney general that the U.S. attorney's office had also chosen not to prosecute a smuggler of undocumented immigrants who has multiple convictions. In his press release, Issa said the man has used more than 21 aliases and has been arrested and deported more than 20 times.

Speaking of the U.S. attorney's office in San Diego, Issa wrote: "They say they don't have resources for these prosecutions but they never ask Congress for help or even tell us what they would need to pursue these cases."

Late last year, San Diego's U.S. Attorney Carol Lam stated: "Our resources are limited and we have numerous and competing enforcement priorities to consider.

"Our office is devoting over a third of our attorney resources to these cases," Lam stated, referring to the prosecution of human smugglers.

Asked Wednesday to comment on the letter and Republicans' ongoing push for stronger immigration-law enforcement, a University of San Diego professor who specializes in cross-border issues said that Republicans and Democrats both agree that the county has reached a point of crisis in its immigration policy.

"No one is happy," said David Shirk, director of University of San Diego's Trans-border Institute, a USD-based group that studies cross-border issues.

However, focusing only on enforcement and prosecution is a mistake, he added.

"We know from experience in other areas like the war on drugs that trying to stop the problem at the border doesn't work," Shirk said. "We are talking about issues that are much more complex —— development issues in Mexico and demand for labor in the U.S.; as long as we don't develop policies that address those two issues, beefing up the border is a Band-Aid solution."

U.S. Rep. Randy "Duke" Cunningham, who also signed the letter to the attorney general, sent a statement to the North County Times on Wednesday saying that the federal government must provide the funding that prosecutors need to prosecute such cases.

"California spends millions prosecuting and detaining illegal aliens and we need to make sure authorities have the resources they need to do their jobs," Cunningham wrote.

Contact staff writer William Finn Bennett at (760) 740-5426 or wbennett@nctimes.com.