Following Tremblay's resignation on November 5, 2012, Applebaum was believed to be a strong contender to win Union Montréal's nomination as its new mayoral candidate. However, he was passed over in favour of councilor
Richard Deschamps. An anonymous colleague told reporters that Applebaum's candidacy had been rejected because his
French language skills were not strong enough to be mayor of an 80 percent
francophone city. He subsequently left Union Montréal to sit as an
independent councillor and submitted his name as an independent mayoral candidate. He argued that in light of the corruption crisis facing the city, notably among the ruling Union Montreal party, the interim mayor should be independent of party affiliation. In the final city council vote on November 16, 2012, Applebaum won 31 votes to Deschamps' 29. He won in part by reaching out more actively than Deschamps to the opposition
Vision Montréal and
Projet Montréal parties and the bloc of independent councillors who resigned from Union Montréal in the same period, most notably by promising to share seats on the
Montreal Executive Committee in a non-partisan
coalition. Applebaum pledged not to run for mayor in the
2013 municipal election, indicating that he would instead run for another term as borough mayor of Côte-des-Neiges–Notre-Dame-de-Grâce. In January 2013, Applebaum announced that the city was creating the
EPIM, a municipal police squad to investigate political corruption in the city. The same day,
Le Devoir reported that the
Charbonneau Commission and
UPAC were investigating Applebaum and had met with Applebaum to investigate his role as borough mayor in zoning modifications and real estate transactions in
Notre-Dame-de-Grace. Applebaum acknowledged the meeting with UPAC and the Charbonneau Commission but denied he was being investigated and refused to disclose the topic of discussion. Subsequent reports from le Devoir revealed that as a city councillor, Applebaum attended a
Union Montreal fundraising event on August 28, 2003, along with Mayor
Gérald Tremblay, Tremblay's brother Marcel, then also a city councillor, and
Frank Zampino, then chairman of the city executive committee. The event was at the La Cantina restaurant on upper St. Laurent Blvd., which was frequented by members of the
Rizzuto crime family, and owned by Federico Del Peschio, who was gunned down in the establishment's parking lot later in 2009. Le Devoir also identified one builder as Tony Magi, a developer with links to the
Rizzuto crime family who had built a condo project on Upper Lachine Rd. in Notre-Dame-de-Grace. The original project required zoning changes opposed by the borough, with a modified version built with $3.4 million in subsidies from the city government. Applebaum again denied any wrongdoing and accused the media of a smear campaign. The fundraiser was organized by real estate developer Lee Lalli, who also had Mafia links and would become friends with Applebaum. Lalli said the evening brought together 20 entrepreneurs who worked for the city and paid $1,000 each to collect $20,000 for Union Montreal. Union Montreal would only declare $12,500. Lalli had also purchased the parcel of land in 1999 for $335 000, applied for zoning changes and the subsidies, and flipped it to Magi in 2005 for $3.2 million, almost matching the city subsidy. On February 19, 2013, 125 police officers from UPAC armed with warrants raided 9 locations in Montreal, including Montreal City Hall and 5 borough offices, including in the Cote-des-Neiges-NDG borough office governed for years by Applebaum. Police said that they spoke with both Applebaum and former mayor Gerald Tremblay. Applebaum continued to deny that he was a target of these investigations. On March 5, 2013, a Radio-Canada investigative report claimed that UPAC was investigating Applebaum's role in a complex land swap for an old orphanage at the corner of boulevard Décarie and chemin de la Côte-Saint-Luc in 2007 involving Lee Lalli and Tony Magi. The report suggested that Applebaum had let Lalli know that the borough was interested in building a borough city hall on the site, an allegation confirmed by Lalli but denied by Applebaum. The Charbonneau Commission had police-taped recordings capturing a 2003 conversation between Vito Rizzuto, then head of the Montreal Mafia, attempting to broker a deal between Lalli and Magi, with the help of councillor
Saulie Zajdel to change the zoning. Lalli would eventually flip the land to build a seniors residence and pharmacy; he would also successfully sue Radio-Canada for defamation for linking him to the mafia. On March 19, 2013, the vice-president of
Dessau, a large Montreal engineering firm with many government contracts, testified before the Charbonneau Commission, exposing a system of bribery with the city of Montreal to ensure city contracts. He described
Frank Zampino, president of the executive committee before Applebaum, as the architect. One of Dessau's subsidiaries, Sogep, was involved in bribing Applebaum in 2010 to win the contract to manage the borough's new sports complex in N.D.G. for three years. In response, on April 26, 2013, Applebaum announced that all companies confessing to bid-rigging at the Charbonneau Commission would be banned from Montreal municipal contracts, regardless of any immunity granted by the Charbonneau Commission. Editorials in the financial community pointed out that such bans made little sense as they punished companies that come clean about past corruption while allowing companies that don't come forward to operate as normal. ==Corruption arrest and trial==