[1] Del Mastro was born to an Italian Canadian family in Peterborough, began high school in Lakefield, and graduated from the Adam Scott Collegiate and Vocational Institute.
[5] Del Mastro won the Conservative nomination for Peterborough over six other contenders in May 2005, defeating former party nominee James Jackson by only eight votes on the final ballot.
[9] Del Mastro planned to participate in a parliamentary delegation to the Middle East organized by the National Council on Canada-Arab Relations in August 2006, during the period of the 2006 Israel-Lebanon conflict.
[10] Some charge that the Prime Minister's Office pressured him not to participate in a trip that would challenge the government's pro-Israel line, although Del Mastro denied this and cited security concerns.
Del Mastro argued that the bill was poorly drafted and could leave the government vulnerable to lawsuits, and said that most Italian Canadians were satisfied with an informal apology issued by Prime Minister Brian Mulroney twenty years earlier.
[13] In 2007, Del Mastro lobbied the Harper government to reopen a passenger train service link from Peterborough to Toronto that was cut by Via Rail seventeen years earlier.
Del Mastro criticized these figures and accused the study's creators of bias, while acknowledging that the project would probably not move forward if assessed solely on the basis of that one report.
[17] Del Mastro has also led a non-partisan House of Commons Rail Caucus and has lobbied for a high-speed link connecting Toronto, Montreal, and Ottawa.
[33][34] During the sentencing hearing held on January 27, 2015, Dean Del Mastro's new lawyer argued that the judge should set aside the previous election overspending guilty verdicts.
[38][39][40] At a hearing on 23 February 2015, prosecution lawyer Tom Lemon stated that Del Mastro's activities "were planned and deliberate and involved a high degree of sophistication".
[50] In 2012, Del Mastro claimed in the House of Commons that the Liberal Party used an American telemarketing firm during the 2011 federal election when it was in fact a Canadian company.
In 2012, veteran CBC parliamentary reporter Kady O'Malley wrote a scathing article accusing Del Mastro of going "in camera" too often thereby contradicting his own party policy of openness and transparency.
[52] While addressing criticism of the digital locks provision within proposed copyright legislation under Bill C-11 (formerly C-32, and C-61 and C-60 before that), Del Mastro compared format-shifting to the act of buying socks from a retailer, only to return later and take a pair of shoes without paying.
In March 2013, New Democratic Party MP Charlie Angus called on Prime Minister Stephen Harper to remove Del Mastro from the Canadian House of Commons Standing Committee on Access to Information, Privacy and Ethics.
[59] Justice Shaughnessy called the former Conservative MP's contravention of election spending limits and deliberate attempts to avoid detection a "grave offence," and ordered Del Mastro to serve the balance of his original sentence.