LOS ANGELES - The wife of the top prosecutor in Los Angeles pleaded no-contest Wednesday to driving without a valid licence, the same day reports emerged that she had an outstanding arrest warrant for failing to appear in court on motor vehicle charges from the 1990s.

City Attorney Rocky Delgadillo had Paris Hilton jailed for violating probation for driving with a suspended licence, then condemned her early release. He said he was embarrassed about the outstanding bench warrant for his wife, the Los Angeles Times newspaper reported Wednesday.

Later in the day, Michelle Delgadillo pleaded no-contest in Los Angeles Superior Court to a misdemeanour charge of driving without a valid licence in connection to a 1998 traffic citation. She was ordered to serve a year of probation and to pay roughly US$500 in fines and penalties, said Santa Monica prosecutor Betty Haviland.

The other charges, which included driving without insurance and in an unregistered car, were dismissed, she said.

Rocky Delgadillo said he didn't know about it until this week and urged his wife to remedy the situation.

"My wife is embarrassed about this and I am embarrassed as well," he said.

His office said she had to pay $431 in fines and penalties.

The couple also has been chronically late in paying fines for at least five parking tickets in the last three years, the newspaper reported. One violation for parking in a red zone in December 2006 was not paid until the newspaper inquired about the tickets last month, by which time the $70 infraction had become a $174 fine with penalties.

A spokesman for Delgadillo said the city attorney's wife was responsible for all the parking tickets and delinquent payments.

The new developments were the latest driving-related issues to dog Delgadillo and his wife.

On Monday, Delgadillo apologized for keeping quiet about a 2004 accident in which his wife crashed his city-issued vehicle while driving on a suspended licence. Delgadillo said he was reimbursing the city for the $1,222 repair.

The prosecutor has said Michelle Delgadillo's offences are not comparable to those of Hilton, who is serving a 45-day sentence for violating her probation in an alcohol-related reckless driving case.

In the latest disclosure, Michelle Delgadillo said she was "very embarrassed."

"I will do whatever the court instructs me to do. I apologize for any embarrassment this has caused my husband and family," she said in a statement to the newspaper.

"It is completely my mistake."

Michelle Delgadillo was cited by a California Highway Patrol officer Aug. 1, 1998, in Santa Monica for allegedly driving with an expired Montana driver's licence, the Times reported, citing court documents.

The citation - issued two weeks before she married Delgadillo and written under her maiden name, Namen - said the tan BMW 325 she was driving had expired tags and she had no proof of insurance.

The Santa Monica city attorney's office filed a three-count criminal case. When she did not appear in court a month later for her arraignment, a judge issued a $2,000 bench warrant, the newspaper reported.