The relationship between Vic Mackey and David Aceveda has evolved in different ways. For the most part Aceveda detests Mackey's brutal tactics while Mackey holds little respect for Aceveda since he is motivated mostly by political ambition. However the two also have a mutual need for each other. Aceveda needed Mackey to keep the crime rate down, while Mackey relied on Aceveda to prevent any major investigations or bad press.
Season One
In the first season, Captain Aceveda was heavily bent out to prove Mackey's guilt, putting out all his effort to take him down. While Mackey detested Aceveda's political ambitions, Aceveda continued to label Mackey as "Al Capone with a badge."
During the beginning of his captaincy, he sought to take down the Strike Team for corruption in the district and assigned Detective Terry Crowley to the team. When Crowley was killed while in the company of Mackey, Aceveda dedicated himself to bringing him down. However, in a bizarre twist of fate, when Assistant Chief Ben Gilroy attempted to sacrifice both Aceveda and Mackey to save his own career, Mackey and Aceveda realized it was in their best interests to work through the problem together. From that point to the end of Aceveda's captaincy, the two maintained an uneasy alliance while still remembering their previous history.
Season Two
At the start of the second season, Aceveda, not wanting a scandal in the midst of his political career, agreed to watch Mackey's back if he could make Strike Team appear to clean up their act and exhibit professionalism at all times possible. Mackey agreed, but the arrangement was soon put under strain by the arrival of Armadillo Quinterno. Both men were horrified at Armadillo's crimes, and Mackey began to use unethical means to put him away, with Aceveda covering up and missteps. Eventually, Aceveda realized that he wasn't doing enough to catch Armadillo, and assigned Claudette to the case, a move Mackey protested because since it might cause his criminal actions to be revealed.
The arrangement held throughout the season, although neither man completely trusted the other. Mackey incorrectly suspected that Aceveda was investigating him, while Aceveda showed obvious suspicion in situations where Mackey might profit from police misconduct. For the most part, Aceveda and Mackey showed mutual respect, although Aceveda did insist on Mackey adding a fifth man to his team.
Toward the end of the season, bad press regarding the barn made it look like Aceveda would lose the election for city council and then be forced out of the department. Leading Mackey to believe that he would soon be rid of his occasional torrmenter. However Aceveda went on to win the primary (which virtually ensured he'd win the election) and Mackey watched in horror as he realized that Aceveda was gaining even more power within the department.
Season Three
The arrangement continued and the two men even began to respect one another, as Mackey managed to keep peace on the street and Aceveda showed that he cared about the well being of farmington and not just about politics. Aceveda was even sympathetic when Mackey came to him pleading for more overtime to pay for medical bills for his kids.
When Dutch reported his suspicions about the Strike Team ripping off the Money Train, Aceveda was initially doubtful since Mackey wasn't showing any signs of newfound wealth. However he later decided to investigate the Strike Team since arresting a corrupt cop would ensure his political future. His investigation would lead to "the incident" where Aceveda was orally raped by two members of the Byz Lats while searching a house for evidence. Eventually Mackey would come to his rescue and Aceveda claimed that he fought the two off before anything happened. Aceveda relentless pursued his attackers, which Mackey assumed was an attempt to connect the Strike Team to the Money Train, since the two attackers also had information which linked the team and the money train cover up.
Season Four
Aceveda left the barn for his Council position but not before writing a scathing letter which would prevent Mackey from ever being promoted. He also went on to warn the new captain Monica Rawlings, but she shrewdly commented that he was more worried about keeping Mackey away from any press-worthy investigations since any misconduct would reflect poorly on the former captain.
The relationship between the two men was destroyed by the letter, and Mackey began to scornfully remark on Aceveda's attempt to muscle in and take credit for Rawling's Asset Seizure program. Their relationship was further undermined when Aceveda brokered a deal that would allow cop-killer Antwon Mitchell immunity from prosecustion in exchange for helping the DEA.
Season Five
Aceveda was approached by IAD Lieutenant Jon Kavanaugh and asked to help investigate Mackey. Aceveda was initially uninterested, but then decided to help after being told that refusal would lead to an investigation into his actions as captain.
Mackey approached Aceveda, and warned him that if the Strike Team went down, they would drag the former captain down with them. He asked Aceveda to monitor the investigation. However Kavanaugh had predicted this action and convinced Aceveda to feed Mackey misinformation. Although Aceveda complied with the lieutenant, he wasn't entirely truthfull to either Kavanaugh or Mackey.
After Lemansky went on the run. Kavanaugh had Aceveda tell Mackey that Lem agreed to turn on the team. Kavanaugh hoped that Mackey and the team would lead him to Lem. Thus ensuring that the whole team would go down for aiding a fugitive. However Shane decided to kill Lem with a grenade, causing everyone to believe it was the Salvadorans.
Season Six
At the end of the sixth season, Aceveda continued to push for progress on the San Marcos killings, a massacre of several Mexican immigrants by unknown assailants, mostly at the behest of Mexican real estate developer Cruz Pezuela, who was also financing his investigation committee into a possible run for mayor. Aceveda also used his political influence to ensure that Mackey was forced into early retirement at an imminent Review Board Hearing. However, events took a wild turn as the graphic photo taken by Juan Lozano of Aceveda's rape suddenly reappeared in the hands of Pezuela, who gave it to Vic as a way to save his job.
Vic attempted to use the photo against Aceveda, only to have it denounced as a fake and to have Aceveda's lawyer threaten him with a lawsuit for slander and blackmail. Mackey later returned with the memory card, the background story of the photo, and all the existing copies. Aceveda was stunned to hear about Cruz Pezuela's involvement in the photo and after listening to Mackey's theory, agreed to help him in his investigation into Pezuela's activities. The scope of the operation stunned the both of them;, Pezuela was helping the Mexican drug cartels buy into Farmington and planned on using various businesses as fronts for money laundering, drug trafficking, and prostitution. Aceveda received the memory card as a symbol of trust between him and Mackey and the two decided to investigate Pezuela, in hopes of shutting his operation down.
Later that evening, Aceveda met with Vic, who had walked out on a Department Review Board hearing and stolen a car full of blackmail material from one of Pezuela's couriers. Aceveda was shocked to learn the dirty secrets of many of the most influential people in Southern California, including public officials, mayoral aides, and the heads of special interest groups. Vic then asked him, "Is this enough to save my job?" Aceveda responded with a look of assent. Letting David take his own vehicle, Vic taunted Pezuela's courier and drove away, knowing that when the car's contents were returned to the right people, it would be more than enough to overturn the Review Board and keep him in charge of the Strike Team.
Season Seven
Vic once again makes an unlikely alliance with Aceveda after first blackmailing Aceveda with images of his rape to the public in order to help him solve a crime ring with possible connections to Lem's and the murder which was actually committed by Shane.