Superficial similarities conceal differences in their leadership styles.

At first glance, the three finalists to become the next chief of the Los Angeles Police Department appear to be cut from the same cloth.

Police Chief William J. Bratton poses with, from left, Deputy Chief Michel Moore, Deputy Chief Charlie Beck and Assistant Chief Jim McDonnell. (Photo: Gary Friedman/Los Angeles Times)

All are middle-aged white men. They are dyed-in-the-wool LAPD cops who came into the department as young men about 30 years ago and took on similar assignments as they rose through the ranks.

Below the surface, however, the similarities give way to distinct differences in leadership, personality and career paths that Assistant Chief Jim McDonnell, Deputy Chief Charlie Beck and Deputy Chief Michel Moore followed to arrive at this decisive point.

Interviews by The Times with the three men, as well as supporters, critics and neutral observers, reveal McDonnell as the LAPD's gracious, well-liked ambassador who has spent the last several years with an eye on the chief's job from his place in the upper reaches of the department as its second in command. Moore is an intense, hard-charging commander who leads with a firm hand, while diligently -- some say obsessively -- running the department's operations in the San Fernando Valley. Beck, laid-back and seemingly unflappable, has surged from the LAPD's middle ranks into the role of reformer under outgoing Chief William J. Bratton.

"One of the strengths that they all share is that they are their own person," Bratton said. "They have their own ideas."

With the finalists selected earlier this week and Mayor Antonio Villaraigosa expected to choose the next chief as early as Monday, department observers have not had a chance to do more than sketch comparisons of the three. In trying to make his decision, the mayor decided Friday evening to call back all three candidates for more interviews this weekend.

Beck, 56, joined the LAPD in 1977. McDonnell, 50, and Moore, 49, signed up four years later. All three spent the first several years of their careers as patrol officers in various parts of the city and, relatively quickly, made the jump to sergeant and took on entry-level supervisor roles. With the city in the grips of the crack cocaine epidemic in the mid-1980s and an understaffed police force failing to keep up with soaring crime rates, it was a rough, eye-opening period to come of age as a young cop.

Each cited experiences during this time that made a deep impression. Within five years on the job, Moore twice found himself in confrontations with armed men and shot them both, killing one. Shortly after the second shooting, he volunteered to work on an anti-drug program with young children. "It was the other side," he said. "It really broadened my sense of what this job is about. I realized that being a police officer is about much more than enforcement."

McDonnell got a first-hand look at the devastation the city was enduring in an anti-gang unit in the LAPD's West Bureau. "The scale of the problem and the desperation of the people involved stayed with me," McDonnell said. "It was the beginning of me understanding that the gang problem in this city is not black and white. I saw kids who were brought up in homes that they didn't get to choose and who were growing up in neighborhoods where gangs were the default family."

Beck worked a similar assignment in South L.A., the epicenter of the city's violence and misery. Like McDonnell, Beck said he was struck in retrospect by how one-dimensional and ineffective the crime-fighting approach was at the time compared to the city's efforts today to link police work with gang intervention and prevention programs. "We were an occupying army," he said. "I saw it not working, but I didn't have the maturity yet as a person or professionally to recognize it and to understand why."

With the exams that officers must pass to qualify for promotions and the internal politics of the LAPD, no one climbs the ranks by chance. These three are no exception, as each has deliberately sought bigger assignments and more responsibility over the years.

Early on, Moore set himself on an ambitious career trajectory, landing an array of positions in the field and in the LAPD's administration offices, which are typically expected of officers who aspire to rise far in the department. He spoke with pride about a stint in the early 1990s in a criminal analysis unit, where he helped develop an early version of the computerized crime mapping systems that are used heavily today.

"It was something I needed to do to round out the look of Michel Moore," he said, adding that the experience offered a stark lesson on the challenge of pushing change on a department entrenched in its ways of doing things.

Many people described Moore as a disciplined leader who demands as much of his staff as he does of himself. He often send e-mails late at night about issues he wants addressed and keeps close tabs on the work he assigns to be done. "Mike Moore is probably the hardest-working deputy chief I ever worked under," said retired Cmdr. Valentino Paniccia, who was Moore's second in command in the Valley. "If anyone is accusing him of being a micromanager" -- and some do -- "it's because they weren't doing their job. Those who aren't doing well get micromanaged. . . . He lets you know he's watching over your shoulder."

Like Moore, McDonnell took on a range of assignments. More than the others, however, he gravitated toward high-level management assignments that landed him in the LAPD's hallways of power instead of at command posts in the department's field stations.

In the mid-1990s, he spent more than two years as a lieutenant running the department's efforts to implement a more community-friendly philosophy. It was an idea that had long received lip service but was never aggressively pursued; the experience, McDonnell said, drove home for him "the power that can come from real collaboration between police and the community."

Several of McDonnell's supporters portrayed him as a serious but kind leader who demonstrates little obvious ego. "I've worked for a lot of different people and I sought Jim McDonnell out as a boss because of his reputation," Capt. Scott Sargent said. "He pays attention to his people. The job is not about him at all."

Throughout his career, Beck has spent most of his time in the field. While not denying an ambition to seek out new and bigger assignments over the years, Beck tended to shun many of the administrative positions that officers typically take to earn promotions. He also has shown less interest in pursuing academics, having only recently earned a bachelor's degree from Cal State Long Beach. By contrast, Moore and McDonnell each have master's degrees.

Beck's evolution as a cop under Bratton is particularly striking. The son of an LAPD deputy chief, he grew up immersed in the old-guard, paramilitary approach to policing.

Soon after Bratton took over the department in 2002, however, he selected Beck to be the captain in charge of the Rampart Division, which had badly tarnished the department with revelations of corruption and abuses.

Beck was hailed by a panel that examined Rampart for his ability to develop -- and get his officers to adopt -- a more inclusive, progressive approach that emphasized a partnership with the residents.

"He puts you at ease as a leader," said Officer Mike Wang, who worked with Beck at Rampart and elsewhere. Beck's calm, hands-off approach can sometimes come across as aloofness to those not familiar with him, Wang acknowledged. "But that's not what's going on. He has an incredible intuition about his cops and what they need. . . . He can relate to you because he's been there."

Inevitably, a shake-up of the department's leadership will follow after the mayor makes his choice as the new chief surrounds himself with people he trusts. It remains to be seen what happens to the two finalists who are not selected.