Politics Now: Union brings in national code of conduct; Harris violated campaign finance laws: Trump team; New poll puts Harris ahead

National secretary Zach Smith has appointed a lawyer to investigate recent allegations against the CFMEU. Donald Trump's team has accused the Vice President of 'the biggest violation' of FEC laws over Biden's leftover campaign cash. 

CFMEU national secretary Zach Smith. Picture: Gary Ramage/NewsWire

Welcome to rolling coverage of the US election following Joe Biden's decision to withdraw from the presidential race.

Here are the key developments you need to know about: 

• Trump team accuses Harris campaign of 'brazen cash grab' and FEC law violations over Biden's campaign cash
• Beyonce gives Harris permission to use her hit 'Freedom' in presidential campaign
• Graphic new video of Trump shooter moments after assassination attempt emerges
• Reuters/Ipsos poll post-Biden's exit shows Kamala Harris leading Donald Trump 44pc to 42pc
• Secret Service advises the Trump campaign not to hold outdoor rallies.
• Kamala Harris declares Trump a 'predator, fraudster, cheat' in her first campaign speech as the Democrats' presumptive nominee for president.
• US Secret Service Director Kimberly Cheatle resigned, a day after acknowledging the agency had failed in its mission to prevent an assassination attempt against Donald Trump. 
• Joe Biden will address the nation and the world at 8pm Wednesday (10am Thursday AEST) from the White House to explain his decision to abandon his presidential campaign.