WASHINGTON — Rudy Giuliani boasts that he reined in crime, welfare and taxes in a city once considered ungovernable.

Those claims are intrinsic to the former New York mayor’s pitch to Republican voters that he has the combination of competence and toughness they want in a president. Whether his record supports those claims, however, is a matter upon which admirers and critics differ markedly.

Most benchmarks during Giuliani’s eight years as mayor, from the start of 1994 to Jan. 1, 2002, suggest dramatic success. The crime rate tumbled by 60 percent. Welfare rolls decreased by 52 percent. Taxes fell by at least 25 percent. While city spending grew, it lagged behind the booming economy of the 1990s.

His record, however, is more complicated than the numbers indicate.

Giuliani was a pugnacious leader. He picked fights with political foes as well as his own police chief and schools superintendent. Any critic — squeegee men, artists, callers to his weekly radio show — was fair game.

In his wake, Giuliani left a trail of detractors who insist he does not deserve all the credit for the good things that happened on his watch.

The city was primed for success as Giuliani took office in 1994.

Thousands of new police officers hired by his predecessor, Democrat David Dinkins, were coming on duty. Thousands of mentally ill homeless people were provided housing and treatment under a program begun by Dinkins and former Democratic Gov. Mario Cuomo.

The economy was growing, pumping billions of dollars into the city treasury. The Dow Jones Industrial Average stood at 3,754.09 on the day Giuliani arrived at City Hall and opened at 10,136.99 the day he left.

“He did some things in the first couple of years in particular that he should get some credit for, particularly the continuing reduction in crime, but I don’t think he was an unusually good mayor,” said Steven Cohen, a public affairs professor at Columbia University.

“He was actually a capable guy and did a good job,” Cohen said. “But I think he had a tendency to see himself as the only person who was smart in the room.”

Giuliani’s signature issue, crime, is especially important to law-and-order Republican voters. Before winning the mayor’s office, Giuliani was a federal prosecutor who put away drug pushers, mob figures and white-collar crooks.

Giuliani was mayor during a period of declining crime rates nationwide. Crime in New York peaked in 1990 and had been dropping for three years before Giuliani took office, according to FBI data. Nationally, violent crime declined 38 percent and property crime declined 33 percent from a modern peak in 1991 through 2005.

The drop was more dramatic in New York. Crime overall decreased by 60 percent between 1993, the year before Giuliani took office, and 2002, when he left. The national crime rate dropped by 24 percent during the same period.

The steep reductions in New York, Giuliani contends, came from a system developed by his police department to map crime patterns and make local police commanders responsible for reducing crime.

“New York City was the only one (of big cities) that had a decline in crime every single year” during that period, Giuliani told Iowa voters recently.

Other big cities copied New York’s program — Compstat, short for computerized, or compare, statistics. Giuliani wrote in his 2002 book, “Leadership,” that he considered it his crown jewel.