— Drafted the legal language for the merger of the old Progressive Conservative party with the Canadian Alliance in 2003.
— Defended the original incorporation of the Conservative Party of Canada from legal challenges.
— Served as lead counsel for the Conservative party during the Gomery inquiry into the federal sponsorship program.
— Represented Doug Finley, the former Conservative campaign director, against Elections Canada charges over the "in-and-out" elections financing scheme in the 2006 election. Charges against Finley and three other individuals were dropped in a plea deal that saw the party plead guilty and pay the maximum fine.
— Handled allegations of inappropriate behaviour against former Conservative cabinet minister Helena Guergis in 2010. Guergis is still pursuing a civil suit against Hamilton and others.
— When Elections Canada contacted the Conservative party in May 2011 about fraudulent phone calls being made to voters, it was Hamilton who responded.
— Hamilton accompanied witnesses when the Commissioner of Elections interviewed them during its continuing investigation into the 2011 campaign robocalls.
— When citizens brought a civil suit against the 2011 election outcome in six ridings, alleging robocalls influenced the vote, Hamilton successfully defended the Conservative MPs. Federal Court Judge Richard Mosley wouldn't overturn the election results but ruled the MPs and their counsel "engaged in trench warfare in an effort to prevent this case from coming to a hearing on the merits."
— Represented the Conservative party in Elections Canada's complaints of 2011 campaign spending problems for former cabinet minister Peter Penashue.
— Handled the secret payment of $13,560 from Conservative party coffers to lawyers representing Mike Duffy last April.