SAN FRANCISCO (AP) — The parents of a San Francisco woman who was fatally shot by a man in the country illegally may have difficulty with their attempts to hold the city legally liable for their daughter's death, legal experts say.

The parents of Kathryn Steinle filed a wrongful death claim Tuesday alleging that the San Francisco Sheriff's Department is to blame for releasing an illegal immigrant from jail despite a federal "detainer" request to keep in custody for possible deportation proceedings. A claim is usually a precursor to a lawsuit. Similar lawsuits blaming so-called "sanctuary city" policies have failed across the country, including a high-profile case in San Francisco.

A state appeals court in 2011 upheld a lower court ruling tossing out the wrongful death lawsuit a family filed against the city for failing to turn over to immigration officials a gang member in the country illegally before he gunned down a father and his two sons. The state appeals court said the policy was not intended to prevent violent crime.

Attorneys also said cities and counties are legally protected from most lawsuits involving police failures to prevent crime.

"It's difficult," said Matt Davis, an attorney who represented the Bologna family. "Cities aren't required to provide police protection."

The claim against San Francisco seeks unspecified damages.

The family and their attorneys also filed two other legal claims seeking unspecified damages from the BLM the U.S. Department of Homeland Security.

The family said it would file lawsuits if the claims are denied.

Legal and gun experts said the family may fare better with their legal claim against the Bureau of Land Management.

The family alleges that a Bureau of Land Management ranger left his loaded service weapon in a backpack in plain view in his car before the weapon was stolen in June.

The semi-automatic pistol was later used in the July 1 killing of 32-year-old Kathryn Steinle.

BLM spokeswoman Martha Maciel said the agency is cooperating with the investigation of the shooting but she declined further comment.

San Francisco officials have 60 days to decide on the claim. Federal authorities have a six-month deadline.

Legal and ballistic experts said the BLM agent appears to have stored the handgun improperly.

"At a minimum, it should have been stored and locked in the trunk, and usually this would be in some type of box or container that is affixed to the vehicle," said Ronald Scott, a Phoenix-based ballistics and weapons experts who teaches safety courses. "Leaving a backpack in a vehicle is like leaving a pocketbook in one. It is an invitation to steal."

The parents said they were filing the legal claims to prevent a similar tragedy. Claims are required to be filed with government agencies before they can be sued.

"We're here not only for Kate, we're here for every citizen of this country who comes to San Francisco," Jim Steinle, the father of the victim, said at a news conference at City Hall. "If you think this can't happen to you, think again."

Juan Francisco Lopez-Sanchez, 45, has pleaded not guilty to a murder charge. He told police he fired the fatal shot accidentally while examining the ranger's gun after finding it under a bench on Pier 14.

The shooting triggered a national debate over immigration after it was revealed that the Sheriff's Department had released Lopez-Sanchez despite a federal request to detain him for possible deportation. Lopez-Sanchez was previously deported five times to his native Mexico. Republican presidential front-runner Donald Trump has repeatedly mentioned Steinle's killing as he calls for a border wall and mass deportations to curb illegal immigration.

Sheriff Ross Mirkarimi said his department was following city law when it released Lopez-Sanchez in April after prosecutors dropped old marijuana possession charges against him.

San Francisco and other cities and counties across the state have enacted so-called "sanctuary city" policies of ignoring so-called detainer requests from Immigration and Customs Enforcement to hold inmates thought to be in the country illegally for deportation proceedings.

The Steinle family claimed the sheriff violated federal laws when he issued a memo in March barring jail staff from communicating with federal immigration officials about detainer requests.

Mirkarimi has said his department requires federal officials to obtain a warrant or some other judicial notice in order for his jail to hold an inmate facing possible deportation.

Sheriff's spokeswoman Kenya Briggs said Mirkarimi can't comment on potential litigation but continues to extend his sympathy to the Steinle family for their loss.

The family also accused ICE, an agency within Homeland Security, of failing to obtain a warrant or judicial notice required by San Francisco to detain and deport Lopez-Sanchez.

"The Director of U.S. Immigration and Customs Enforcement (ICE) met recently with members of the Steinle family to express the agency's profound sympathy for their loss," spokeswoman Virginia Kice said.