McManus' first term was due to end at the end of this year. And the city council was in the process of reappointing him. However, McManus had recently expressed feelings of job insecurity, and had said he was considering his options.
Last week, McManus played his cards close to his vest when talking about the opportunity in Texas.
"San Antonio is a nice city. It's a large city. I'm not just jumping at anything that comes down the pike," McManus said last week. "Again, this is the only opportunity that I had looked at in a number that have crossed my path in the last five or six months."
Mayor R.T. Rybak says he's sorry to see McManus leave, but he was not caught off guard. Rybak says he began preparing for the possibility of losing the chief a few weeks ago.
Rybak says he's been developing a succession plan to ensure that the department runs smoothly while the city looks for another chief.
"I've been meeting with and speaking with councilmembers and their staffs over the past couple of weeks as this became a possibility," says Rybak. "We have, I think, a good clear consensus as where to move on that. I think everybody recognizes that we have to keep continuity and keep the focus on public safety."
Rybak says his succession plan will focus on internal candidates. Some say Assistant Chief Tim Dolan is a natural choice for interim chief, since he already has experience handling day-to-day matters for McManus.
Rybak wouldn't speculate on who the interim will be, but he says he says there are good prospects within the department.
"Chief McManus brought some fresh energy and some good new ideas into the department, and helped us launch some new intiatives that were best done with someone with a fresh perspective," says Rybak. "Right now what we need to do is complete that work, and we have some great leadership within the department."
McManus received a favorable performance review after his first year as chief. Councilmembers gave him high marks for his visibility in the community and for his work to diversify the upper ranks of the department. In June 2005 he promoted two African Americans to the ranks of inspector and deputy chief.
City councilmember Don Samuels says he's devastated by the loss of McManus. Samuels represents the 5th Ward in north Minneapolis, where several neighborhoods are hotspots for crime. He says McManus had the confidence of many of his constituents.
Samuels says the qualities that made him popular in Minneapolis were bound to attract others.
"I totally understand that a chief that has the profile as a forward-looking chief of the future would be in high demand, and people would be lined up to seduce him with very attractive offers," says Samuels. "I understand that, and I think it's one of the prices you pay for getting somebody like that."
But some say it wasn't so much that McManus was lured away as he was pushed out. Some members of the Police Community Relations Council -- the group of community leaders and police officials charged with implementing a federally mediated agreement formed in 2003 -- blame Mayor R.T. Rybak.
The Rev. Ian Bethel is one of the co-chairs of the PCRC, and says he considers McManus a friend. He says he advised McManus to leave Minneapolis because of the political climate.
"What we have is a result of Mayor Rybak not being as straightforward as he should have been immediately after his reelection, and during the campaign process," says Bethel.
Fellow PCRC member Ron Edwards agrees with Bethel's assessment. He says he believes the relationship between the mayor and chief began to go south after Rybak was reelected last November.
Edwards says he attended a meeting with the mayor and the chief right after the election. He says members of the PCRC asked the mayor if he was ready to reappoint Chief McManus.
"In that meeting in which William McManus was present, the mayor very coldly and calculatingly, indicated that that was a premature discussion and consideration at that point," says Edwards.
Edwards says the remark seemed to stun McManus.
Mayor Rybak says he remembers the meeting very differently.
"He had support here, behind closed doors and in public. And the chief chose to leave in spite of the fact that he had strong support from me and from others," Rybak says. "I wish him well, I enjoyed working with him. But I do think we have very good leadership and can keep moving."
Rybak is expected to name his choice for interim chief very soon. The interim chief will serve for 90 days while the city begins its search for a new chief.